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If cosA + sinA = √2cosA, then prove that cosA - sinA = √2sinA
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If cosA + sinA = √2cosA, then prove that cosA - sinA = √2sinA
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If cosA + sinA = √2cosA, then prove that cosA - sinA = √2sinA
Given: cosA sinA = √2cosA
To Prove: cosA - sinA = √2sinA

Proof:
We can start by using the trigonometric identity: (cosA - sinA)^2 = cos^2 A + sin^2 A - 2sinAcosA.

Now, we need to manipulate the given equation to get it in a form that we can use to substitute into the identity above.

cosA sinA = √2cosA
Dividing both sides by cosA, we get:
sinA = √2

Now, substituting sinA = √2 into the equation, we get:
cosA √2 = √2cosA

Simplifying this, we get:
cosA = sinA

Now, we can substitute cosA = sinA into the identity above:
(cosA - sinA)^2 = cos^2 A + sin^2 A - 2sinAcosA
(sinA - sinA)^2 = sin^2 A + sin^2 A - 2sin^2 A

Simplifying this, we get:
0 = sin^2 A - sin^2 A
0 = 0

This is true, which means that our original equation is true. Therefore, we have proven that:
cosA - sinA = √2sinA
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If cosA + sinA = √2cosA, then prove that cosA - sinA = √2sinA
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