Question

show that√2cos (45-A) = cas A sinA.
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Answer 1

root 2 cos(45-A)=cosA+sinA

By fundamental law,

root2(cos 45 cos A + sin 45 sinA)

root 2(1/root 2 cosA +1/root 2 sinA)

root2(1/root2)(cosA+ sinA)

cosA+ sinA

Answer 2

Answer:

multiplying and divide LHS √2

Step-by-step explanation:

√2 (1/√2 sin A + 1/√2 cos A)

and sin 45 = cos 45 = 1/√2

=> √2 (sin 45 sin A + cos 45 cos A)

=> √2 cos (45-A)