How do you verify the identity $cosx+sinxtanx=sec x$ ?

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Answer 1 · 2015-05-01T11:42:37

Use the fact that:
$tanx=sinx/cosx$
and
$secx-1/cosx$
So:
$cosx+sinxsinx/cosx=1/cosx$
$(cos^2x+sin^2x)/(cosx)=1/cosx$
$1/(cosx)=1/cosx$

Where I used: $sin^2x+cos^2x=1$

How do you verify the identity cosx+sinxtanx=sec xcosx+sinxtanx=sec x?