How do you solve cosx=sinx?

1 Answer
Aug 9, 2016

pi/4 or 45^@

Explanation:

Property of complementary arcs -->
cos x = sin (pi/2 - x)
There for,
sin x = sin (pi/2 - x)
a. x = (pi/2 - x) --> 2x = pi/2 --> x = pi/4
b. x = pi - (pi/2 - x) = pi/2 + x (Rejected as non-sense)

Answer: x = pi/4 or 45^@
Check.
x = pi/4 --> sin x = sqrt2/2 --> cos x = sqrt2/2 . OK