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July 22, 2014

July 22, 2014

Posted by **Shym** on Sunday, June 3, 2007 at 4:29am.

secA-tanA=1/4. Find cosA

I got: CosA=4(1-sinA) Is my answer good?

Now multply each side by (1+sinA)

CosA(1+sinA)=4 cos^2 A

CosA=1/4 (1+sinA)

16(1-sinA)=1+sinA

15=17SinA

So you have sinA, now find Cos A from your equation you originally solved.

- Maths -
**Reddy**, Saturday, June 29, 2013 at 6:21amCos A= 4(1-(15/17))

cos A= 4(12/17)

Cos A= 48/17

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