[tex]\sec^2 x \csc^2 x = \dfrac{1}{\cos^2 x}{\dfrac{1}{\sin^2x} = \dfrac{1}{\cos^2 x \sin ^2 x}[/tex]
a
[tex]\sec^2x + \csc^2 x = \dfrac{1}{\cos^2 x} + {\dfrac{1}{\sin^2x} =\dfrac{\sin^2 x + \cos^2x}{\cos^2x \sin^2 x} = \dfrac{1}{\cos^2 x\sin^2 x}[/tex]
Those are equal.
b.
[tex]\cos^2 x + \sin ^2x = 1[/tex]
That's not equal, choose B
c.
[tex]\sec^2x + \sec^2x \cot^2 x = \sec^2 x(1 + \cos^2 x/\sin^2x) = \sec^2x ( (\sin^2 x+\cos^2x)/\sin^2 = \sec^2x \csc^2 x [/tex]
That's equal.
d. That's equal too
Answer: B
