Question

If x=cos teta + sin teta,y=cos teta-sin teta then x^2+y^2=2 prove it

Answer 1

Answer:

As LHS = RHS, the following equation is verified.

Step-by-step explanation:

LHS

x^2 + y^2

(cosΘ + sinΘ)^2 + (cosΘ - sinΘ)^2

(sin^2 + cos^2 + 2sinΘcosΘ) + (cos^2 + sin^2 -2sinΘcosΘ)

2sin^2 + 2cos^2

2 * ( sin^2 + cos^2)

*property: sin^2 + cos^2 = 1*

So,

2*(1)

2

TAKE RHS

2