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sin A = 5 / 13 and cos B = 4 /5

Hence find the value of tan (A-B), strictly in fractional form as above, where

tan(A-B) = tan A - tan B / 1 + tan A and B

For a friend so [manuel on] I Know nothing [/manuel off]

Dieseldog

ajm

I'll start you off. It makes it easy if you imagine the fractions are the sides of a triangle:

1) Sin A = opposite / hypotenuse = 5 / 13

the other remaining side (Adjacent) must be sqrt(13^2 - 5^2) = 12 (using pythagorus)

therefore Tan A = Opposite / Adjacent = 5/12

2) Cos B = Adjacent / Hypotenuse = 4 / 5

Opposite must be 3 (classic 3,4,5 triangle)

so tan B = 3/4

Now stick them into your formula for tan(a-b)

Luminous

iTrader: (3)

You learn something new every day

+Doc+

thanks ajm, even though I dont know what the hell your talking about

T4molie

Christ I used to know how to do that stuff, can't feckin remember now

ajm

Has your 'friend' completed the problem now then?

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Ive left it with him, I dont think hes logged on yet.