Question

If cos theta + sin theta = root 2 sin theta,show that sin theta - cos theta = root 2 cos theta.​

Answer 1

Answer:

Here is your solution....

Answer 2

Answer:

Step-by-step explanation:

sin²A+cos²A=1                 (a)

sinA+cosA=√2

let sinA-cosA =y

sin²A - cos²A =(sinA+cosA)(sinA-cosA)=√2 × y         (b)

adding (a),(b)

2sin²A=√2y+1

===>y = (2sin²A -1)/√2 = (1-2cos²A)/√2 = -cos2A/√2