Possible solutions as exact values for cos theta=1/sqrt(2) ?

1 Answer
Jun 13, 2018

t = pi/4 + 2kpi
t = (7pi)/4 + 2kpi

Explanation:

cos t = 1/sqrt2 = sqrt2/2
Trig table and unit circle give 2 solutions for t:
t = +- pi/4 + 2kpi
Note.
t = - pi/4 is co-terminal to t = (7pi)/4
Answers:
t = pi/4 + 2kpi
t = (7pi)/4 + 2kpi