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Been stuck since last night

so I give up plase help me with this

Prove that

Cot2x+cosec2X=cotX

done these

1/(tan2x+sin2x)

1/( (2tanx/(1-tan^2 x)) + 2sinx cosx)

after that I made the domenators(sP?) the same

so that 1/ (2 tanx +2sinxcosx-2sin x cosx tan^2 x)/(1-tan^2 x)

now the 1- tan ^ 2 x becomes the nomenator(sp?)

so (1- tan^2 x)/2tanx + 2sinx cosx -2sinx cosx tan^2 x

after going this far I seem to do something really stupid and get lost between the numbers not knowing how to go back...pleaase help me

so I give up plase help me with this

Prove that

Cot2x+cosec2X=cotX

done these

1/(tan2x+sin2x)

1/( (2tanx/(1-tan^2 x)) + 2sinx cosx)

after that I made the domenators(sP?) the same

so that 1/ (2 tanx +2sinxcosx-2sin x cosx tan^2 x)/(1-tan^2 x)

now the 1- tan ^ 2 x becomes the nomenator(sp?)

so (1- tan^2 x)/2tanx + 2sinx cosx -2sinx cosx tan^2 x

after going this far I seem to do something really stupid and get lost between the numbers not knowing how to go back...pleaase help me

habosh

Prove that

Cot2x+cosec2X=cotX

Cot2x+cosec2X=cotX

LHS = Cot2x + cosec2X =

1/tan2x + 1/sin2x =

cos2x/sin2x + 1/sin2x =

cos2x/2sinxcosx + 1/2sinxcosx =

(cos2x + 1)/2sinxcosx =

(2cos^2x - 1 + 1)/2sinxcosx =

2cos^2x/2sinxcosx =

cos^2x/sinxcosx =

cosx/sinx =

1/tanx =

cotx =

RHS

QED

Invisible

LHS = Cot2x + cosec2X =

1/tan2x + 1/sin2x =

cos2x/sin2x + 1/sin2x =

cos2x/2sinxcosx + 1/2sinxcosx =

(cos2x + 1)/2sinxcosx =

(2cos^2x - 1 + 1)/2sinxcosx =

2cos^2x/2sinxcosx =

cos^2x/sinxcosx =

cosx/sinx =

1/tanx =

cotx =

RHS

QED

1/tan2x + 1/sin2x =

cos2x/sin2x + 1/sin2x =

cos2x/2sinxcosx + 1/2sinxcosx =

(cos2x + 1)/2sinxcosx =

(2cos^2x - 1 + 1)/2sinxcosx =

2cos^2x/2sinxcosx =

cos^2x/sinxcosx =

cosx/sinx =

1/tanx =

cotx =

RHS

QED

I solved it in another way but I got the answer right ...I don't get why 1/tan2x = cos2x/sin2x....I've never saw that in my heinemann book

thanx anyway

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