Simplify and write the trigonometric expression in terms of sine and cosine:
?
So I came up with this
= 1/f(u)
But I am not sure what to do or if I am right?
Basically, if you have two complementary angles $\displaystyle \alpha$ and $\displaystyle \beta$, i.e.:
$\displaystyle \alpha+\beta=\frac{\pi}{2}$
then a trig. function whose argument is one of the angles will be equal to its co-function evaluated at the other. That is:
$\displaystyle \sin(\alpha)=\cos(\beta)$
$\displaystyle \cos(\alpha)=\sin(\beta)$
$\displaystyle \tan(\alpha)=\cot(\beta)$
$\displaystyle \cot(\alpha)=\tan(\beta)$
$\displaystyle \sec(\alpha)=\csc(\beta)$
$\displaystyle \csc(\alpha)=\sec(\beta)$
$\displaystyle \frac{a}{b} + \frac{b}{a}$
common denominator is $\displaystyle a \cdot b$
$\displaystyle \frac{a \cdot a}{a \cdot b} + \frac{b \cdot b}{a \cdot b}$
$\displaystyle \frac{a^2}{ab} + \frac{b^2}{ab}$
$\displaystyle \frac{a^2+b^2}{ab}$