Can someone please prove this equation:

Cos x+Cos x= 2Sec x

1 - Sin x 1 + Sin x

Printable View

- Sep 8th 2010, 04:33 PMGAVREED2Trigonometry Proof
Can someone please prove this equation:

__Cos x__+__Cos x__= 2Sec x

1 - Sin x 1 + Sin x - Sep 8th 2010, 04:39 PMskeeter
- Sep 8th 2010, 10:48 PMGAVREED2
I'm not sure if i completed the question correctly

Is the answer 2/cos x = 2/cos x - Sep 8th 2010, 11:36 PMUnknown008
You should consider only one hand side and should end up with 2sec(x).

Expand, simplify.

Ultimately, you should get;

- Sep 9th 2010, 02:23 AMEducated
Yes, the answer is but that is not how you solve a prove question.

There is no point in saying 2/cos x = 2/cos x, because of course that equation is true, and what you have basicly done is rewritten 2sec(x) in the form 2/cos(x).

You should start off on the left, ignoring the right hand side, having only the equation and simplifying/rearranging it to match what is stated.

You must show the steps of how you got that, without the answer of 2sec(x) in the equation:

Continue simplifying/rearranging it to get 2sec(x).

Hint: ( )