Question

What are the different GENERAL AND DOUBLE ANGLE IDENTITIES?
in trigonometry

Answer 1

@whpalmer4 @Callisto @dalia_lam @thomaster @Yttrium

Answer 2

just a minute... im going to scan something for you

Answer 3

okay

Answer 4

\[\sin2x = 2sinxcosx\]
\[\cos 2x = \cos^2x - \sin^2x = 2\cos^2x - 1 = 1 - 2\sin^2x\]
\[\tan2x = \frac{ 2tanx }{ 1-\tan^2x }\]

Answer 5

thx :)

Answer 6

that's awesome! @csscgirl

how do you use the sum and difference identities?
there are 2 signs. what do you use first

Answer 7

if you use sum, notice that the addition symbol is on top at first, go through the problem, and use the symbols that are on top (the symbol may be + ontop of -, or sometimes - on top of +), because it might change to subtraction. If you are doing difference, use the symbols that are on the bottom. hopefully that made sinse, if not, i can tryto explain it differently

Answer 8

okay thanks
got it

Answer 9

ok :) great :) your welcome

Answer 10

@csscgirl, what you did may be breaking a copyright. Unless you write that book yourself, it's probably copyrighted. At least state the book you copied it from.

Answer 11

ok... Glencoe Advanced Mathematical Concepts Precalculus with Applications