Difference between revisions of "2021 AMC 12B Problems/Problem 13"
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==Solution== | ==Solution== | ||
+ | First, move terms to get <math>1+5cos3x=3sinx</math>. After graphing, we find that there are <math>\boxed{6}</math> solutions (two in each period of <math>5cos3x</math>). -dstanz5 | ||
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+ | == Video Solution by OmegaLearn (Using Sine and Cosine Graph) == | ||
+ | https://youtu.be/toBOpc6vS6s | ||
− | + | ~ pi_is_3.14 | |
==See Also== | ==See Also== | ||
{{AMC12 box|year=2021|ab=B|num-b=12|num-a=14}} | {{AMC12 box|year=2021|ab=B|num-b=12|num-a=14}} | ||
{{MAA Notice}} | {{MAA Notice}} |
Revision as of 21:54, 11 February 2021
Contents
[hide]Problem
How many values of in the interval satisfy
Solution
First, move terms to get . After graphing, we find that there are solutions (two in each period of ). -dstanz5
Video Solution by OmegaLearn (Using Sine and Cosine Graph)
~ pi_is_3.14
See Also
2021 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 12 |
Followed by Problem 14 |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | |
All AMC 12 Problems and Solutions |
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