a) express in term of X :

b) Find:

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- February 4th 2007, 11:54 AMviettangent of inverse trignometric function
a) express in term of X :

b) Find: - February 4th 2007, 12:48 PMSoroban
Hello, viet!

Quote:

a) Express in term of : .

We will need the identity: .

Recall that an inverse trig value is an__angle__.

Let

Since , we have:

. . and Pythagorus gives us:

Hence: .

The problem becomes: .

. . . . . .

Quote:

b) Find: .

We have: .

Then: .

. . Hence: .

And: .

. . Hence: .

The problem becomes: .

Multiply top and bottom by

I hope I didn't make any stupid blunders . . . - February 4th 2007, 06:23 PMthedoge
I used your method for part B on a similar problem and it is not working.

numbers were 5/6 for the sin, 5/9 for the cos.

ended with (((5/sqrt(11))+(sqrt(56)/5))/(1-(5/sqrt(11))*(sqrt(56)/5)))*sqrt(11)

but it is wrong - February 4th 2007, 07:41 PMSoroban
Hello, thedoge!

Quote:

I used your method for part B on a similar problem and it is not working.

Numbers were 5/6 for the sin, 5/9 for the cos.

Ended with: (((5/sqrt(11))+(sqrt(56)/5))/(1-(5/sqrt(11))*(sqrt(56)/5)))*sqrt(11) .**??**

but it is wrong

Evidently, your preliminary work is correct.

. .

Identity: .

We have: .

Multiply top and bottom by

- February 4th 2007, 07:46 PMthedoge
Ah ok. Thank you:)