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: Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = �� – 3, 6 + 6 = ��.
problem_activity: Narrative
The purpose of this activity is for students to use what they know about making a ten to identify which addition expressions are equivalent to
\(10 + n\)
expressions. Students should have access to double 10-frames and connecting cubes or two-color counters.
The Compare Stage 2 Addition Cards will be used again in a later lesson.
Required Materials
Materials to Gather
Connecting cubes or two-color counters
Double 10-frames
Materials to Copy
Compare Stage 2 Addition Cards to 20
Required Preparation
Create a set of Compare Stage 2 Addition Cards to 20 from the blackline master for each group of 3.
Launch
Groups of 3
Give each group a set of cards and access to double 10-frames and connecting cubes or two-color counters.
Activity
Read the task statement.
8 minutes: small-group work
Student Facing
Take out all the expression cards that have the number 10.
Mix up the rest of the cards.
Pick a card.
Place the card under the expression with 10 that it is equal to.
[IMG]
Student Response
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Activity Synthesis
“We are going to create a poster and do a Gallery Walk.”


aligns: no