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tcasey0478
Prove the identity showing each step as rule. secx-sinxtanx=cosx
try changing everyhthing to sin and cos 1 / cos x -( sin x * sinx) / cos x =(1 - sin^2 x) / cos x and what is (1 - sin^x) equal to ?
I don't understand the step "=(1 - sin^2 x) / cos x" What rule is used to get here?
I see it now, they share a common denominator of cosx so they are combined, thank you.