Difference between revisions of "1979 AHSME Problems/Problem 20"
(→Problem 20) |
(→SOLUTION) |
||
Line 9: | Line 9: | ||
\textbf{(E) }\frac{\pi}{6}</math> | \textbf{(E) }\frac{\pi}{6}</math> | ||
− | == | + | ==Solution== |
Solution by e_power_pi_times_i | Solution by e_power_pi_times_i | ||
Latest revision as of 15:51, 17 June 2021
Problem #20
If and then the radian measure of equals
Solution
Solution by e_power_pi_times_i
Since , . Now we evaluate and . Denote and such that . Then , and simplifying gives . So and . The question asks for , so we try to find in terms of and . Using the angle addition formula for , we get that . Plugging and in, we have . Simplifying, , so in radians is .
See also
1979 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 19 |
Followed by Problem 21 | |
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 • 26 • 27 • 28 • 29 • 30 | ||
All AHSME Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.