Question

cos(2x+25) csc(x+20)=1

Answer 1

Recuerda que:

$\sin(x) = \cos(90 - x)$

$\csc(x) = \frac{1}{ \sin(x) }$

Aplicandolo:

$\cos(2x + 25) \frac{1}{ \sin(x + 20) } = 1 \\ \cos(2x + 25) = \sin(x + 20) \\ \cos(2x + 25) = \cos(70 - x) \\ 2x + 25 = 70 - x \\ 3x = 45 \\ x = 15$