Question

use the identities:
cos2x-cos^2x=0
2sinxtanx-tanx=1-2sinx
4sin^2x+2cos^2x=3
please help me! please

Answer 1

Are you trying to solve for x?

Answer 2

no i want the left side of the problem to equal whats on the right
for the first one i need the left side to be solved so that the answer results in zero just like the right side

Answer 3

It actually is what I meant

Answer 4

oh right sorry i miss understood

Answer 5

Did the question gives any range for x?

Answer 6

no they dont

Answer 7

Then I shall assume x has an infinite amount of solutions

Answer 8

yeah

Answer 9

cos (2x) - cos^2 x = 0
By the double-angle formula, cos (2x) = 2 cos^2 x - 1.
2 cos^2 x - 1 - cos^2 x = 0
cos^2 x - 1 = 0
cos^2 x = 1
cos x = 1 or cos x = -1
x = 2n pi or x = (2n + 1)pi
where n is an element of the set of integers.

Answer 10

I am starting to wonder if they require ambiguous values or specific values as answers

Answer 11

the only thing it said was solve by using the identities

Answer 12

Do you need help with factoring the expressions or solving for x or both?

Answer 13

i do... so the first one it correct? with the second

Answer 14

is there a way we can only solve by through identities and not factoing

Answer 15

2 sin x tan x - tan x = 1 - 2 sin x
tan x(2 sin x - 1) = 1 - 2 sin x
tan x(2 sin x - 1) + (2 sin x - 1) = 0
(tan x + 1)(2 sin x - 1) = 0
tan x = -1 or sin x = 0.5

Answer 16

Really, the second question seems easier to just factorise, in fact, I don't even know if using identities can help to solve this one

Answer 17

could we change tan tp sin/cos

Answer 18

Tried that and felt like I am straying off

Answer 19

2sinx*sinx/cosx-sinx/cosx=....

Answer 20

2sin^2x/cos-sinx/cosx

Answer 21

sin^2x/cosx

Answer 22

could it work out like this

Answer 23

2 sin^2 x / cos x - sin x / cos x = 1 - 2 sin x
2 sin^2 x - sin x = cos x - 2 sin x cos x
2 sin^2 x - sin x = cos x - sin (2x)
1 - cos (2x) - sin x = cos x - sin (2x)
It all seems weird to me

Answer 24

your right i will stick with factoring... and the last one can you please help me with that one please

Answer 25

4 sin^2 x + 2 cos^2 x = 3
4 sin^2 x + 2(1 - sin^2 x) = 3
4 sin^2 x + 2 - 2 sin^2 x = 3
2 sin^2 x = 1
sin^2 x = 0.5
sin x = sqrt 0.5 or sin x = -sqrt 0.5

Answer 26

oh okay and you switched 2cos identity?

Answer 27

You should probably just write the identities on a piece of paper

Answer 28

sin^2 x + cos^2 x = 1
cos^2 x = 1 - sin^2 x

Answer 29

im doing that right now...thank you so much!