Question

simplify: cos(2x-y)cosy-sin(2x-y)siny

Answer 1

cos 2x

Answer 2

how??

Answer 3

cos (A+B)= cosAcosB - sinAsinB

Answer 4

if u plug in A = 2x -y and B=y
u get the same form

Answer 5

woah thanks!

Answer 6

noprob

Answer 7

find all solutions in the interval [0,2pie) 3sin(2t-pie)=3

Answer 8

sin (2t-pi) = 1
2t - pi = pi/2, 5pi/2....
2t = 3pi/2, 7pi/2
t=3pi/4,7pi/4..and so on..there might be one more solution..check for more

Answer 9

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