Question

Find all solutions to the equation.

7 sin^2x - 14 sin x + 2 = -5

Answer 1

substitute sin(x) with u

Answer 2

Let sin(x) be y, solve the equation in terms of y then find the sine of the solutions.

Answer 3

so the equation would be like this

7u^2 -14u +2 = -5

Answer 4

u^2 -2u +1 =0

Answer 5

solve for u

Answer 6

then let sin(x) = u [you found (u) already ]

Answer 7

solve for (x) then

Answer 8

So, I got for u: (u-1)(u-1)...
What do I do now... I'm confused. :-/
(and, thank you for the help!!)

Answer 9

any time

Answer 10

so you have (u-1)^2 = 0

Answer 11

that means u-1 = 0

Answer 12

=> u = 1

Answer 13

So, that is the solution for the equation?? I'm done?

Answer 14

nope

Answer 15

now Let Sin(x) = u = 1

Answer 16

solve for (x)

Answer 17

if Sin(x) = 1 then x= ......

Answer 18

so x = 1/sin ??

Answer 19

nope

Answer 20

or simply x= pi/2

Answer 21

x is an angle

Answer 22

So, x = pi/2.... Are there any more solutions? I'm so sorry... I stink at math! :P

Answer 23

i attached the complete solutions

Answer 24

but simply u can say x = pi/2

Answer 25

Oh, okay!! Thank you so much for your help!!! :)