# Math Help - 3 solving trig equations

1. ## 3 solving trig equations

1.) $tan(x)=1/sqrt(3)$

2.) $sin(x)^2=1/25$
now i know that this is actually $sin(x)=1/5$.

3.) $2sin(x)cos(x)+sin(x)-2cos(x)-1=0$

2. Originally Posted by rarrrettt111
1.) $tan(x)=1/sqrt(3)$

2.) $sin(x)^2=1/25$
now i know that this is actually $sin(x)=1/5$.

3.) $2sin(x)cos(x)+sin(x)-2cos(x)-1=0$

(1) $tan30=1/sqrt(3)$
special angles , it is positive so x = 30 , 210

(2) $sin(x)=1/5$
11.54 is the basic angle , X should be in the first and second quadrant as it is positive .

(3)
sin x -1 = 2 cos x - 2 sinx cos x
sin x-1 = 2 cos x ( 1 - sinx )
1 - sinx = - 2 cosX(1-sin x)
1 = -2cos X
cos X = - 1/2
X = 120 and 240
(3)