Step-by-step explanation: sinθ+cosθ= 2 cosθ To prove:- cosθ+sinθ= 2 sinθ Proof:- sinθ+cosθ= 2 cosθ Squaring both sides, we get sin 2 θ+cos 2 θ+2sinθcosθ=2cos 2 θ ⇒sin 2 θ−cos 2 θ+2sinθcosθ=0 Subtracting 2sin 2 θ both sides, we have −sin 2 θ−cos 2 θ+2sinθcosθ=−2sin 2 θ sin 2 θ+cos 2 θ−2sinθcosθ=2sin 2 θ (cosθ−sinθ) 2 =2sin 2 θ ⇒cosθ−sinθ= 2 sinθ Hence proved. Reply
Step-by-step explanation:
sinθ+cosθ=
2
cosθ
To prove:- cosθ+sinθ=
2
sinθ
Proof:-
sinθ+cosθ=
2
cosθ
Squaring both sides, we get
sin
2
θ+cos
2
θ+2sinθcosθ=2cos
2
θ
⇒sin
2
θ−cos
2
θ+2sinθcosθ=0
Subtracting 2sin
2
θ both sides, we have
−sin
2
θ−cos
2
θ+2sinθcosθ=−2sin
2
θ
sin
2
θ+cos
2
θ−2sinθcosθ=2sin
2
θ
(cosθ−sinθ)
2
=2sin
2
θ
⇒cosθ−sinθ=
2
sinθ
Hence proved.