Question

Simplify the trigonometric expression
(sec x + tan x)(sec x - tan x)

Answer 1

FOIL it

Answer 2

Does (sec x)(tan x) =sinx/cosx?

Answer 3

Did you Foil it? because you should just get it so the OI cancel out... so your left with secx^2 - tanx^2.. which i believe is an identity so the answer should just be 1

Answer 4

How is secx^2 - tanx^2 an identity?

Answer 5

tanx^2 + 1 = secx^2 if you rearrange that you will see that the equation above is just 1

Answer 6

http://math2.org/math/trig/identities.htm

Answer 7

You understand what FOIL is correct?

Answer 8

Yes

Answer 9

Okie good =)