Question

If cos 4 theta + sin 5 theta = 2 then find solutions

Answer 1

Answer:

Step-by-step explanation:

The value of sin and cos ranges from (-1) to 1. According to question,

cos 4x + sin 5x=2 ( let theta be x)

since both sin and cos has maximum value as 1

so, to become 2 both cos 4x and sin 5x have to become 1.

Thus,

cos 4x=1

so, 4x=0 deg. or 360 deg

so, x=0 or 90 deg

and sin 5x=1

so, 5x=90 or 450 deg

so, x=18 or 90 deg

since for x=90 deg both the functions became 1 so, x or theta =90 deg