# Math Help - A couple questions...Help please.

1. ## A couple questions...Help please.

Hey everybody I have a couple questions, most of them I have the answers for but a couple I don't I really hope someone can help me with the questions. Thanks

1. Solve the equation: -1/8cos^-1(x) + tan^-1(-1)= -pi/3

For the answer I got x=cos(46pi/3) again if anyone can verify this?

The cos^-1 mean the inverse of cos, the same gos for tan^-1.

The second question is

2. Find the equation of the parabola in the form y=a(x-h)^2+K that has a focus at (1,2) and whose directrix is y=0. Hint: Consider the points (x,2) their distance from the directrix.

for this question I got the equation, y=1/4(x-1)^2+1. This answer I am not really sure about.

I have two more questions but I think I'll stop with these because I feel that I am getting greedy.

Again thanks to anybody that helps me get these answers verified.

2. Originally Posted by Altami
Hey everybody I have a couple questions, most of them I have the answers for but a couple I don't I really hope someone can help me with the questions. Thanks

1. Solve the equation: -1/8cos^-1(x) + tan^-1(-1)= -pi/3

For the answer I got x=cos(46pi/3) again if anyone can verify this?

The cos^-1 mean the inverse of cos, the same gos for tan^-1.

The second question is

2. Find the equation of the parabola in the form y=a(x-h)^2+K that has a focus at (1,2) and whose directrix is y=0. Hint: Consider the points (x,2) their distance from the directrix.

for this question I got the equation, y=1/4(x-1)^2+1. This answer I am not really sure about.

I have two more questions but I think I'll stop with these because I feel that I am getting greedy.

Again thanks to anybody that helps me get these answers verified.

$-\frac{1}{8}\cos^{-1}(x) + \tan^{-1}(-1)= -\frac{\pi}{3}$

$-\frac{1}{8}\cos^{-1}(x) - \frac{\pi}{4} = -\frac{\pi}{3}$

$-\frac{1}{8}\cos^{-1}(x) = -\frac{\pi}{12}
$

$\cos^{-1}(x) = \frac{2\pi}{3}$

$x = -\frac{1}{2}$

3. Thanks, skeeter. I really wasn't sure about either one to tell you the truth. But I am assuming that the second one is correct?