# Pre-Calculus

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A.Verify the identity.
B.Determine if the identity is true for the given value of x. Explain.

Sec(x) / tan(x) = tan(x) / [tan(x) – cos(x)],x = π

I already solved A and I believe it's true; however, I need help with B.

• Pre-Calculus -

clearly B is false at x=π

Sec(x) / tan(x) = tan(x) / [tan(x) – cos(x)]
(-1)/0 = 0/(0-(-1)) = 0/1
-∞ = 0

I don't think so!

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