Thursday, December 4, 2014

Prove csc^2 x + sec^2 x = csc^2 x sec^2 xRS shows the 2 sets being multiplied.

csc^2 x + sec^2 x = csc^2 x * sec^2
x


We will start from the left side and prove the right
side.


We know that:


csc(x) =
1/sin(x) ==> csc^2 x = 1/sin^2 x


sec(x) = 1/cos(x)
==> sec^2 x = 1/cos^2 x


We will
substitute:


==> (1/sin^2 x) + (1/cos^2
x)


Now we will rewrite using the common denominator (sin^2
x*cos^2 x)


==> (cos^2 x + sin^2 x) / (sin^2 x* cos^2
x)


Now we know that sin^2 x + cos^2 x =
1


==> 1 / (sin^2 x *cos^2
x)


==> 1/sin^2 x  *  1/cos^2
x


==> csc^2 x * sec^2 x
...................q.e.d

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