few_shots: Example 1:
Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Mathematical concept/skill options: 
A. Prove and apply trigonometric identities.
B. Model periodic phenomena with trigonometric functions.
C. Interpret functions that arise in applications in terms of the context.
D. Build a function that models a relationship between two quantities.
E. Define, evaluate, and compare functions.
F. Use functions to model relationships between quantities.
G. Understand the concept of a function and use function notation.
H. Analyze functions using different representations.
I. Extend the domain of trigonometric functions using the unit circle.
J. Interpret expressions for functions in terms of the situation they model.
K. Build new functions from existing functions.
L. Construct and compare linear and exponential models and solve problems.


Thought: This problem applies trigonometric identities, including the angle addition formula for cosine.
Answer: A

Example 2:
Problem/activity:
Task
Solve the quadratic equation
$$ x^2 = (2x - 9)^2 $$
using as many different methods as possible.


Mathematical concept/skill options: 
A. Apply and extend previous understandings of arithmetic to algebraic expressions.
B. Write expressions in equivalent forms to solve problems.
C. Understand solving equations as a process of reasoning and explain the reasoning.
D. Use the four operations with whole numbers to solve problems.
E. Generate and analyze patterns.
F. Understand and apply properties of operations and the relationship between addition and subtraction.
G. Use properties of operations to generate equivalent expressions.
H. Solve real-life and mathematical problems using numerical and algebraic expressions and equations.
I. Represent and analyze quantitative relationships between dependent and independent variables.
J. Understand properties of multiplication and the relationship between multiplication and division.
K. Work with equal groups of objects to gain foundations for multiplication.
L. Represent and solve problems involving multiplication and division.
M. Solve problems involving the four operations, and identify and explain patterns in arithmetic.
N. Work with radicals and integer exponents.
O. Interpret the structure of expressions.
P. Solve equations and inequalities in one variable.
Q. Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from.
R. Multiply and divide within 100.
S. Represent and solve problems involving addition and subtraction.
T. Use polynomial identities to solve problems.
U. Represent and solve equations and inequalities graphically.
V. Understand the connections between proportional relationships, lines, and linear equations.
W. Reason about and solve one-variable equations and inequalities.
X. Rewrite rational expressions.
Y. Understand the relationship between zeros and factors of polynomials.
Z. Perform arithmetic operations on polynomials.
AA. Create equations that describe numbers or relationships
AB. Analyze and solve linear equations and pairs of simultaneous linear equations.
AC. Gain familiarity with factors and multiples.
AD. Write and interpret numerical expressions.
AE. Add and subtract within 20.
AF. Work with addition and subtraction equations.
AG. Solve systems of equations.
AH. Analyze patterns and relationships.


Thought: This task asks students to solve an equation in one variable. Since the problem asks for many different solution methods, students are also encouraged to solve the problem graphically.
Answer: P, U

Example 3:
Problem/activity:
Task
Suppose $A$ is an angle with vertex $P$, as pictured below:
[IMG]
Draw a circle with center $P$ and with  radius $r \gt 0$.  Explain why the circle
meets each ray of angle $A$ in a single point.  Label these points $Q$ and $R$ respectively.
Draw circles with centers $Q$ and $R$ respectively and radius $r$.  These circles meet at $P$ and a second point to be labelled $B$.
Show that ray $\overrightarrow{PB}$  bisects angle $P$.


Mathematical concept/skill options: 
A. Apply trigonometry to general triangles.
B. Understand similarity in terms of similarity transformations.
C. Analyze, compare, create, and compose shapes.
D. Prove geometric theorems.
E. Make geometric constructions.
F. Graph points on the coordinate plane to solve real-world and mathematical problems.
G. Understand congruence and similarity using physical models, transparencies, or geometry software.
H. Understand congruence in terms of rigid motions.
I. Draw, construct, and describe geometrical figures and describe the relationships between them.
J. Translate between the geometric description and the equation for a conic section.
K. Reason with shapes and their attributes.
L. Prove theorems involving similarity.
M. Explain volume formulas and use them to solve problems.
N. Find arc lengths and areas of sectors of circles.
O. Define trigonometric ratios and solve problems involving right triangles.
P. Use coordinates to prove simple geometric theorems algebraically.
Q. Visualize relationships between two-dimensional and three-dimensional objects.
R. Solve real-life and mathematical problems involving angle measure, area, surface area, and volume.
S. Understand and apply theorems about circles.
T. Identify and describe shapes (squares, circles, triangles, rectangles, hexagons, cubes, cones, cylinders, and spheres).
U. Solve real-world and mathematical problems involving volume of cylinders, cones, and spheres.
V. Classify two-dimensional figures into categories based on their properties.
W. Apply geometric concepts in modeling situations.
X. Solve real-world and mathematical problems involving area, surface area, and volume.
Y. Experiment with transformations in the plane.
Z. Understand and apply the Pythagorean Theorem.
AA. Draw and identify lines and angles, and classify shapes by properties of their lines and angles.


Thought: This task asks students to make geometric constructions, such as bisecting an angle.
Answer: E

Now, assign the following problem or activity to one or more relevant mathematical concepts/skills it teaches.
shot_info: fl_problem_001894

HS_0

im_task_000870

HS_1

im_task_001160

HS_2
options: Solve systems of equations.

Solve equations and inequalities in one variable.

Solve real-life and mathematical problems using numerical and algebraic expressions and equations.

Use the four operations with whole numbers to solve problems.

Work with equal groups of objects to gain foundations for multiplication.

Analyze patterns and relationships.

Add and subtract within 20.

Work with addition and subtraction equations.

Understand solving equations as a process of reasoning and explain the reasoning.

Write expressions in equivalent forms to solve problems.

Represent and solve problems involving multiplication and division.

Represent and analyze quantitative relationships between dependent and independent variables.

Rewrite rational expressions.

Generate and analyze patterns.

Write and interpret numerical expressions.

Understand and apply properties of operations and the relationship between addition and subtraction.

Interpret the structure of expressions.

Work with radicals and integer exponents.

Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from.

Solve problems involving the four operations, and identify and explain patterns in arithmetic.

Represent and solve equations and inequalities graphically.

Use properties of operations to generate equivalent expressions.

Apply and extend previous understandings of arithmetic to algebraic expressions.

Understand the connections between proportional relationships, lines, and linear equations.

Analyze and solve linear equations and pairs of simultaneous linear equations.

Reason about and solve one-variable equations and inequalities.

Gain familiarity with factors and multiples.

Understand the relationship between zeros and factors of polynomials.

Perform arithmetic operations on polynomials.

Create equations that describe numbers or relationships

Represent and solve problems involving addition and subtraction.

Use polynomial identities to solve problems.

Understand properties of multiplication and the relationship between multiplication and division.

Multiply and divide within 100.
problem_activity: Activity
In earlier activities, students wrote expressions to describe visual patterns by first creating tables and reasoning repeatedly about how the pattern changes at incrementally greater step numbers. Here they write an equation to describe a pattern without creating a table of values. They look more directly at the structure of the visual pattern and its connections to the parts of the equations, and then reason in the other direction: given an equation, they generate a visual pattern. Students also begin to frame the relationship between the quantities as a function with inputs and outputs leading to a definition of
quadratic function
.
Some students are likely to view the
\(n\)
th step of the given pattern as an
\(n\)
-by-
\(n\)
square with four small squares added at the corners, leading to the expression
\(n^2 + 4\)
for the total number of small squares. Others may view this as an
\(n+2\)
by
\(n+2\)
square with 4 rectangles removed, each consisting of
\(n\)
squares. The latter leads to the (equivalent) expression
\((n+2)^2 - 4n\)
. In the next activity, students will look closely at how equivalent expressions arise when analyzing geometric patterns, but if equivalent expressions come up in this activity, consider inviting students to share them.
This prompt gives students opportunities to see and make use of structure (MP7) when writing an equation from a visual pattern. The specific structure they might notice is an inner square with a side length equal to the step number along with a small square on each corner. Later, generating a pattern given an equation requires them to reason abstractly and concretely (MP2).
Launch
Give students a moment to observe the pattern from the activity and ask them what they notice and what they wonder. Then, ask students to sketch the next step in the pattern and share their sketch with a partner.
Representation: Internalize Comprehension.
Activate or supply background knowledge. Provide students with access to a simple two-column graphic organizer in which one column is for what they know and one column is for what they wonder. Allow students to organize their thinking this way for each step of the visual pattern.
Supports accessibility for: Visual-spatial processing; Organization
Student Facing
[IMG]
If the pattern continues, what will we see in Step 5 and Step 18?
Sketch or describe the figure in each of these steps.
How many small squares are in each of these steps? Explain how you know.
Write an equation to represent the relationship between the step number
\(n\)
and the number of squares
\(y\)
. Be prepared to explain how each part of your equation relates to the pattern. (If you get stuck, try making a table.)
Sketch the first 3 steps of a pattern that can be represented by the equation
\(y = n^2 - 1\)
.
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Student Facing
Are you ready for more?
For the original step pattern in the statement, write an equation to represent the relationship between the step number
\(n\)
and the perimeter,
\(P\)
.
For the step pattern you created in part 3 of the activity, write an equation to represent the relationship between the step number
\(n\)
and the perimeter,
\(P\)
.
Are these linear functions?
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Extension Student Response.
Anticipated Misconceptions
Some students may wonder how to draw a pattern given the equation
\(y=n^2-1\)
.  Show them the warm-up problems where they subtracted 1 to remove the small square in Figure B and added 1 when there was an extra small square in Figure C.  Prompt them to describe subtracting 1 as removing one small square from each step.  Some students may find it easier to start drawing step 2 or step 3.  They can work backwards to draw step 1 which would have 0 squares since
\(1^2-1=0\)
.  Emphasize that making a table can help them figure out exactly how many small squares are needed in each step.
Activity Synthesis
Make sure students see the connection between the equation
\(y=n^2 +4\)
and composition of the squares in the pattern: that regardless of what
\(n\)
is, the figure at Step
\(n\)
is composed of a square that is
\(n\)
by
\(n\)
, plus 4 small squares at each corner.
Next, help students relate the work so far to the idea of functions. Discuss with students:
“In each pattern we’ve seen, is the relationship between the step number and the number of squares a function? How do you know?” (Yes. The step number is the input, and the number of squares is the output. For every step number, there is a particular number of squares.)
“How can the relationship be expressed using function notation?” (If the function
\(f\)
gives the number of squares at step number
\(n\)
, we can define it as
\(f(n) = n^2+4\)
.)
Introduce
quadratic function
as a function that is defined by a quadratic expression. Like other functions, it can be represented with an equation, a table of values, a graph, and a description.
Conversing: MLR2 Collect and Display.
Prepare students for the discussion by inviting them to first explain to a partner how each part of their equation relates to the pattern. Record the words, phrases, and diagrams students use to explain the equations they wrote to represent the pattern. Display the collected language for all to see, and invite students to borrow from, or add more language to the display throughout the remainder of the lesson. This will help students read and use mathematical language during partner and whole-class discussions.
Design Principle(s): Optimize output (for explanation); Maximize meta-awareness


correct_option_index: 16