How do you prove: $Cosx + sinx tanx = secx$ ?

Question

40702 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-03-04T05:03:03

See below.

We have:

$LHS=cosx+sinxtanx$ and $RHS=secx$

We change the $LHS$ :

$cosx+sinx*sinx/cosx$

$= cosx+sin^2x/cosx$

$= (sin^2x+cos^2x)/cosx$

$= 1/cosx$

$= secx$

So $LHS=RHS$

Hence, proved.

How do you prove: Cosx + sinx tanx = secxCosx + sinx tanx = secx?