Tanx/1-cotx+cotx/1-tanx=?

2 Answers
Mar 29, 2018

tanx/(1-cotx)+ cotx/(1-tanx)

=(tanx(-tanx))/((1-cotx)(-tanx))+ cotx/(1-tanx)

= (- tan^2x)/(1-tanx) +cotx/(1-tanx) [because" tanx xx cotx = 1]

=(cotx-tan^2x)/(1-tanx)

=(1/tanx-tan^2x)/(1-tanx)

=(1-tan^3x)/(tanx(1-tanx))

=((1-tanx)(1+tanx+tan^2x))/(tanx(1-tanx))

=((1+tanx+tan^2x))/(tanx)

=1/tanx+tanx/tanx+tan^2x/tanx)

=color(red)(1+tanx+cotx

=1+ sinx/cosx + cosx/sinx

=(sinxcosx + sin^2x + cos^2x)/ (sinxcosx)

=color(red)((sinxcosx + 1)/ (sinxcosx)

= 1 + 1/(sinxcosx)

= 1 + 2/(2sinxcosx)

=color(red)( 1 + 2/(sin2x)

The final answer may vary, depending on where you may wanna stop :)

Mar 29, 2018

tanx/(1-cotx)+cotx/(1-tanx)=secxcscx+1.

Explanation:

tanx/(1-cotx)+cotx/(1-tanx),

=(sinx/cosx)/(1-cosx/sinx)+(cosx/sinx)/(1-sinx/cosx),

={sinx/cosx-:(sinx-cosx)/sinx}+{cosx/sinx-:(cosx-sinx)/cosx},

={sinx/cosx xx sinx/(sinx-cosx)}+{cosx/sinx xx cosx/(cosx-sinx)},

=sin^2x/{cosx(sinx-cosx)}-cos^2x/{sinx(sinx-cosx)},

=1/(sinx-cosx){sin^2x/cosx-cos^2x/sinx},

=1/(sinx-cosx){(sin^3x-cos^3x)/(sinxcosx)},

=1/cancel((sinx-cosx)){cancel((sinx-cosx))(sin^2x+sinxcosx+cos^2x)}/(sinxcosx),

={(sin^2x+cos^2x)+sinxcosx}/(sinxcosx),

=(1+sinxcosx)/(sinxcosx),

=1/(sinxcosx)+(sinxcosx)/(sinxcosx),

=1/sinx*1/cosx+1,

rArr tanx/(1-cotx)+cotx/(1-tanx)=secxcscx+1.