I have a trig proof i have come at from every way i can think of and just can't make it work If a/sin A = b/cos A, show that sin A cos A = (ab)/(a^2 + b^2) thanks
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Originally Posted by jacs I have a trig proof i have come at from every way i can think of and just can't make it work If a/sin A = b/cos A, show that sin A cos A = (ab)/(a^2 + b^2) thanks $\displaystyle \displaystyle\frac{a}{SinA}=\frac{b}{CosA}\Rightar row\ \frac{a}{b}=\frac{SinA}{CosA},\ \frac{b}{a}=\frac{CosA}{SinA}$ Then $\displaystyle \displaystyle\frac{a}{b}+\frac{b}{a}=\frac{a^2+b^2 }{ab}$ Work that out and invert the result.
Thanks, figured it out now. Never would have thought to do it that way on my own!