# Math Help - [SOLVED] Trig Function

1. ## [SOLVED] Trig Function

Suppose cot = 3 in the 3rd quadrant.

I know that tan = 1/3 and than both sin and cos are negative, but i can't figure out what the values for them are.

I tried sin = 1/3cos and then

cos^2 + 1/9cos^2 = 1

cos^2 = 8/9

cos = -2sqrt(2)/3 but then i keep getting the wrong answer. Can someone help me find sin and cos please

2. Originally Posted by goliath
Suppose cot = 3 in the 3rd quadrant.

I know that tan = 1/3 and than both sin and cos are negative, but i can't figure out what the values for them are.

I tried sin = 1/3cos and then

cos^2 + 1/9cos^2 = 1

cos^2 = 8/9

cos = -2sqrt(2)/3 but then i keep getting the wrong answer. Can someone help me find sin and cos please
use the identity ...

$\tan^2{x} + 1 = \sec^2{x} = \frac{1}{\cos^2{x}}$

3. Using $\tan \theta = \frac{1}{3}$ you can find the long side of the triangle using pythagora's theorem.

$h^2 = 1^2+3^2$

Then you can find the solutions to the remaining problems.