I've been working at proving these identites and I just cant seem to figure them out, some of them just come to me others I work on them for 10 mintues or more and just get more and more bogged down.(adsbygoogle = window.adsbygoogle || []).push({});

1) csc2x + cot2x = cotx so far i have

1/sin2x + cos2x/sin2x = cosx/sinx

1+cos2x/sinx = cosx/sinx

2) cos^2x + 4cosx + 3 = cosx + 3 so far i have

4cos^2x + 3 = cosx + 3

3)1+cosx/1-cosx - 1-cosx/1+cosx = 4cotxcscx so far i have

1+cosx/sin^2x - sin^2x/1+cosx = 4cosx/4sinx*1/sinx

4)cos^2x-csc^2x/cot^2x = sin^2x - sec^2x so far i have

cos^2x - 1/sin^2x/ cos^2X/sin^2x

cos^2x - 1/sin^2x * sin^2X/cos^2x

cos^2x - 1/cos^2x

cos^2x - sec^2x

5) 1 + sec^2x + cot^2x/ csc^2x = sec^2x

1+ 1/cos^2x + cos^2x/sin^2x/ 1/sin^2x = 1/cos^2x

6) sin(x+y) + sin(x-y)/cos(x+y) + cos(x-y) = tanx

I have absolutely no clue what to do with this one, i've tried changing the left side to cosxsiny+sinxcosy and stuff like that but it just doesnt come to me

Thanks for any help given to me, I really need some and greatly appreciate it!

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# Homework Help: Proving Identities and Double angles problems

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