# Thread: Trig ratios, other trig mapping questions :/ Help greatly appreciated

1. ## Trig ratios, other trig mapping questions :/ Help greatly appreciated

Hey folks. Few questions here. A reply in detail ASAP = insanely appreciated.

1. If sin a = y/r ; write the other 5 trigonometric ratios for a.

2. If csc B = -14/10 ; and B is in the fourth quadrant. Find the coordinate of the point on the end of the terminal arm, and its principle angle. Then find all the trigonometric ratios for B.

[t graph here]

(( I know it might be a challenge to find a graph but if you could upload one to imageshack or something or just explain it, It'd be great help ))

3. If (weird symbol, I think theta) * is third quadrant angle and cot * = -15/-8, find:

a) sin * cos *
b) cos^2 *
c) 4 cot *
d) cot * tan *

Once again thank you SO much for reading and helping! Need this for tommorow before I get behind!

2. Well for number 1
The other 5 trig ratios are cos a, tan a, sec a, cosec a, cot a
Trigonometric functions - Wikipedia, the free encyclopedia
See that link for more detail
$\displaystyle sin a =\frac{y}{r}$

$\displaystyle cos a=\sqrt{1-sin^2a}$
cos a$\displaystyle =\sqrt{1-\frac{y^2}{r^2}}$

$\displaystyle tan a=\frac{\frac{y}{r}}{\sqrt{1-\frac{y^2}{r^2}}}$

$\displaystyle cosec a=\frac{r}{y}$

$\displaystyle sec a=\frac{1}{\sqrt{1-\frac{y^2}{r^2}}}$

$\displaystyle cot a=\frac{\sqrt{1-\frac{y^2}{r^2}}}{\frac{y}{r}}$

3. Thank you, (thanks) now I just need the last 2, tyvm

4. Originally Posted by Luciffer
Thank you, (thanks) now I just need the last 2, tyvm
Show us what you have been able to do, given the solution to the first problem.

-Dan

5. Originally Posted by topsquark
Show us what you have been able to do, given the solution to the first problem.

-Dan
Lol, he didn't explain how he got there so I learned nothing. Wikipedia page didn't get me anywhere. I basically know little about trig outside of the basics. bah

6. Originally Posted by Luciffer
Lol, he didn't explain how he got there so I learned nothing. Wikipedia page didn't get me anywhere. I basically know little about trig outside of the basics. bah
You need not anything other than basic trig to solve these. Use the definitions of these functions and the fact that $\displaystyle cos^2(x)+sin^2(x) \equiv 1$ to solve the others, and if you have trouble doing so, show what you've done and we will help you.

$\displaystyle sinA = \frac{y}{r}$

this looks too much like what is given in text books where y is the sin
x is cos then r is the radius or hypotenuse

then $\displaystyle cosA = \frac{x}{r}$ and etc

just my take anyway.....