few_shots: 
Example:
Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

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


Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

Now, assess whether the following problem or activity is 'aligned' with the given Common Core standard in Mathematics.

shot_info: fl_problem_001894_pos_0

HS_0
standard_description: Use numbers expressed in the form of a single digit times an integer power of 10 to estimate very large or very small quantities, and to express how many times as much one is than the other. For example, estimate the population of the United States as 3 × 108 and the population of the world as 7 × 109, and determine that the world population is more than 20 times larger.
problem_activity: Narrative
The purpose of this How Many Do You See is for students to use grouping strategies to describe the images they see.
When students use grouping to find the total in a multiple of tens, they look for and make use of structure (MP7).
Launch
Groups of 2
“How many do you see? How do you see them?”
Flash the image.
30 seconds: quiet think time
Activity
Display the image.
“Discuss your thinking with your partner.”
1 minute: partner discussion
Record responses.
Student Facing
How many do you see? How do you see them?
[IMG]
Student Response
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Activity Synthesis
“What expressions could we record for the different ways that students saw the tens?” (
\(6 \times 10\)
, because some students saw 6 groups of 10.
\(3 \times (10 \times 2)\)
, because some students saw 2 rows of 10, then multiplied by 3.
\((3 \times 10) \times 2\)
, because some students multiplied 3 times 10 for each column, then multiplied by 2.)
Consider asking:
“Who can restate in different words the way _____ saw the tens?”
“Did anyone see the tens the same way but would explain it differently?”
“Does anyone want to add an observation to the way _____ saw the tens?”


aligns: no