Posted by **anon** on Thursday, March 3, 2011 at 1:35am.

Write equivalent equations in the form of inverse functions for

a.)x=y+cos è

b.)cosy=x^2

(can you show how you would solve)

a.)

x= y+ cos è

cos è = x-y

theta = cos^-1(x-y)

b.)

cosy=x^2

cos(y) = x^2

y = Cos^-1(x^2)

- Trigonometry -
**MathMate**, Thursday, March 3, 2011 at 8:31am
They are both correct!

- Trigonometry -
**Reiny**, Thursday, March 3, 2011 at 8:34am
in a) is è a variable or a constant.

If it is a variable then we don't find an "inverse"

(the inverse is found by interchanging the x and y variables in a 2 variable relation)

in b)

original : cosy = x^2

inverse: cosx = y^2

solving this for y:

y = ±√cosx,

solving this for x:

x = cos^-1 (y^2) , where -1 < y < 1

- Trigonometry -
**MathMate**, Thursday, March 3, 2011 at 1:17pm
Reiny, I interpret "inverse" being inverse trigonometric function, since he is doing a trigonometry course. However, I stand to be corrected!

- Trigonometry -
**Reiny**, Thursday, March 3, 2011 at 3:06pm
You are right.

Funny how one's mind can get stuck along one track, and other possibilities get blocked.

## Answer this Question

## Related Questions

- Trigonometry (repost Reiny) - at 1:35am I posted ; Write equivalent equations in...
- Trigonometry(please Clarify) - I posted before ; Write equivalent equations in ...
- Math - Suppose f(x) = sin(pi*cosx) On any interval where the inverse function y...
- Math - Trigonometry - Let f(x) be a polynomial such that f(cos theta) = cos(4 ...
- calc - what is the derivative of sinx- cosy = 0 in its simplest form? I got to ...
- maths (trigonometry) - please solve these if possible Q1. If sinx +siny=3(cosy-...
- algebra - Can someone please help me do this problem? That would be great! ...
- Trigonometry - Okay, I have been given a trigonometric equation to solve (sin^2(...
- Math - Solving Trig Equations - Solve each equation for o is less than and/or ...
- Trigo help! - Ok, i've tried this question, and it brings me to no answers. ...