Question

(sin theta +cos theta ) ²+(cos theta-sin theta) ²​

Answer 1

Answer:

= (sin theta^2 + cos theta^2 + sin theta×cos theta) + ( cos theta^2 + sin theta^2 - sin theta^2)

= (1 + sin theta×cos theta) + (1 - sin theta×cos theta )

= 2

Answer 2

As we know

sinθ+cosθ=1

(sinθ+cosθ)²+(cosθ-sinθ)²

(a+b)²=a²+2ab+b²

sin²θ+2 sinθcosθ+ cos²θ+cos²θ-2cosθsinθ+sin²θ

1+1

2