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lizzie177
Nov 15, 2009, 12:37 PM
Hello, I am stuck on my math homework, and if you could help me out, that would be greatly appreciated!
Ok, so evaluate the following expressions, giving exact value answers ( not decimals)

a) tan^2 (3pie/4)

b) sec^2 (7pie/6)

Thank you :D

KISS
Nov 15, 2009, 12:53 PM
The answers are 1 and 4/3. OK, now what.

tan = sin(x)/cos(x); you can concert things to degrees if you want to e.g. = 3/4*360; then do a tan(x)*tan(x)

for the sec one, use the identity. Convert to to degrees and normalize (so degrees are between 0 and 360). You can subtract n *2*PI initially or convert it to degrees and subtract n-360