Question

Prove that: (sin theta + sin 3theta + sin 5theta)/(cos theta + cos 3theta + cos 5theta) = tan 3theta ​

Answer 1

Answer:

Step-by-step explanation:( sin x + sin 3x + sin 5x ) / ( cos x + cos 3x + cos 5x )

= [ ( sin 5x + sin x ) + sin 3x ] / [ ( cos 5x + cos x ) + cos 3x ]

= [ ( 2 sin 3x cos x ) + sin 3x ] / [ ( 2 cos 3x cos x ) + cos 3x ]

= [ sin 3x ( 2 cos x + 1 ) ] / [ cos 3x ( 2 cos x + 1 ) ]

= sin 3x / cos 3x

= tan 3x

hence proved

PLS MARK AS BRAINLIST!!