Question

Need help for trigo.. fan and medal given!

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[2(cos x)^2 - 1] (sec x)^2 = 2 - (sec x)^2

Answer 1

ok first u need to know this basic indentity
\[secx=\frac{ 1 }{ cosx }\]

Answer 2

\[(2\cos ^{2}x-1)\sec ^{2}x = 2-\sec ^{2}x\]

Answer 3

are u familiar with this?

Answer 4

i know that

Answer 5

ya o.o

Answer 6

ok so just multiply

Answer 7

i did..

Answer 8

=.=

Answer 9

\[(2\cos^2x-1)\sec^2x=2\cos^2x.\sec^2x-\sec^2x\]
right?

Answer 10

oh ok i got it

Answer 11

thanks ! :)

Answer 12

yw!!!

Answer 13

fanned and medaled ! :D thank yew!

Answer 14

happy to help ya :)