# Math Help - Inv. Trig Function

1. ## Inv. Trig Function

If you want to find a value for X from which

$sin^-1(x) = 0.8$

I have graphed this, and is $X = .916$

2. Originally Posted by ADY
If you want to find a value for X from which

$sin^-1(x) = 0.8$

I have graphed this, and is $X = .916$

Your post makes no sense.

If you want to solve $\sin^{-1}x = 0.8 \Rightarrow x = \sin 0.8$ then use a calculator. I get x = 0.717 (correct to 3 decimal places) assuming you're measuring angle in radians.

Otherwise, please post the question exctaly as it appears in your book or wherever it is you got it from.

3. Apologises Mr F.

I was just clearly mashing the keypad lol.

Ok, so lets try again.

Explain how i can use the inv. trig functions on my calc to find a value of X. From $sin(X) = 0.8$

Thanks

4. Originally Posted by ADY
Apologises Mr F.

I was just clearly mashing the keypad lol.

Ok, so lets try again.

Explain how i can use the inv. trig functions on my calc to find a value of X. From $sin(X) = 0.8$

Thanks
$\sin x = 0.8 \Rightarrow x = \sin^{-1} (0.8) = 0.927$ radians.