Question

If sec theta + tan theta = x, then sec theta = ?

Answer 1

a) (x^2 + 1)/ x
b) (x^2 - 1)/ x
c) (x^2 - 1)/ 2x
d) (x^2 + 1)/ 2x

Answer 2

Instead if theta I will consider A
(Theta is too long to write

Answer 3

Okiee xD

Answer 4

secA+ tanA = x

tanA= x-secA ...(1)

Now we know that:

sec²A=1+tan²A

Put in eqn (1):

sec²A=1+ (x-secA)²

sec²A = 1+x²+sec²A -2xsecA

0=1-2xsecA

2xsecA=1

secA= 1/2x

Answer 5

Oh

Answer 6

Thanks a lot! But that's not an option. ;-;

Answer 7

That's what I am wondering

Answer 8

I am right, but no option there with that answer.

Answer 9

The options are probably wrong ;-;

Answer 10

No!
I got it!

Answer 11

I did a mistake

Answer 12

secA+ tanA = x

tanA= x-secA ...(1)

Now we know that:

sec²A=1+tan²A

Put in eqn (1):

sec²A=1+ (x-secA)²

sec²A = 1+x²+sec²A -2xsecA

0=1-2xsecA + x²

2xsecA=1 + x²

secA= 1+x²/2x

Answer 13

Here it is ↑↑↑

Answer 14

I forgot to add x² in 6th step

Answer 15

Thanks a lot, Divya! I appreciate it! I'm kinda noob in trig. ;-;

Answer 16

That's option D

Answer 17

Heh! np ^_^

Answer 18

c: