Question

How is sin square x minus cos square x is equal to minus cos 2x?

Answer 1

Answer:

see the attachment.

hope it helped.

Mark me as BRAINLIEST

and follow me.

Answer 2

Answer: sin square x minus cos square x is equal to minus cos 2x.

Step-by-step explanation:

$cos(2x) = cos(x+x)$

Using the formula : cos(A + B) = cosAcosB - sinAsinB

Here,

A = x

B = x

⇒  $cos(2x) = cos(x)cos(x) - sin(x)sin(x)$

⇒  $cos(2x) = cos^{2} (x) - sin^{2} (x)$

⇒  $cos^{2} (x) - sin^{2} (x) = cos(2x)$

Multiplying both sides by -1 we get,

⇒  $-cos^{2} (x) + sin^{2} (x) = -cos(2x)$

⇒  $sin^{2} (x) -cos^{2} (x) = -cos(2x)$

       LHS  =  RHS

Hence proved.

#SPJ2