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


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

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, does the following problem or activity enable students to learn the full intent of the following concept or skill?

shot_info: fl_problem_001894_pos_0

HS_0
standard_description: Write numbers from 0 to 20. Represent a number of objects with a written numeral 0-20 (with 0 representing a count of no objects).
problem_activity: Narrative
The purpose of this warm-up is to elicit the idea that there can be a connection between drawings and expressions, which will be useful when students interpret the numbers and symbols in an expression in relation to drawings. While students may notice and wonder many things about the image and expression, the important discussion points are that there are 3 red counters and the number 3 and that there is 1 yellow counter and the number 1.
Launch
Groups of 2
Display the image.
“What do you notice? What do you wonder?”
1 minute: quiet think time
Activity
“Discuss your thinking with your partner.”
1 minute: partner discussion
Share and record responses.
Student Facing
What do you notice?
What do you wonder?
[IMG]
Student Response
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Activity Synthesis
“How many counters are there? How do you see them?” (4. I see 1 yellow  counter and 3 red counters.)
“In the next activity, we will match expressions to drawings.”


aligns: no