Question

find the value of θ, if sin5θ=cos4θ where 5θ and 4θ is an acute angle. also give solution very fast

Answer 1

Answer:

θ = 10°

Step-by-step explanation:

Given: sin5θ = cos4θ

=> sin5θ = sin(90 - 4θ)

=> 5θ = 90 - 4θ

=> 5θ + 4θ = 90

=> 9θ = 90

=> θ = 10°

Hope it helps!

Answer 2

Step-by-step explanation:

we know,

sin∅ = cos( 90- ∅) use , this here,

cos( 90° - 5∅) = cos4∅

we also know ,

if CosA = cosB

then,

A = B use, this

(90 -5∅) = 4∅

90° = 5∅ + 4∅

90° = 9∅

∅ = 90°/9 = 10°