1. ## solving trigonometric equations

for 0<a<360 i need to find 'a' from sec^2(a) = 4tan(a)-2 any help would be much appreciated thanks

2. Rewrite:

$1-tan^{2}(a)=4tan(a)-2$

Now, bring it all to one side and make a u sub to turn it into a quadratic.

Let u=tan(a)

3. ## Sec and tan

Shouldn't that be
$1+tan^2(a)=4tan(a)-2$?

You can remember it by starting with
$sin^2(a)+cos^2(a)=1$
and then dividing both sides by $cos^2(a)$
to get
$tan^2(a)+1=sec^2(a)$