Question #004aa

1 Answer
Nov 20, 2017

The two sides are not equivalent.

Explanation:

(1-cos(theta))(1+sec(theta))=sin^2(theta)

Using FOIL, multiply out the left hand side.

1+sec(theta)-cos(theta)-cos(theta)sec(theta)

Convert the sec

1 +1/cos(theta)-cos(theta)-cos(theta) 1/cos(theta)

cancel(1 )+ 1/cos(theta) - cos(theta) - cancel(1)

1/cos(theta) - cos^2(theta)/cos(theta)

(1-cos^2(theta))/cos(theta)

sin^2(theta)/cos(theta) or sin(theta)tan(theta)

This is not equivalent to the right hand side, sin^2(theta). You can also see that they are not equivalent by looking at the graphs of both sides.

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