(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If [tex]m^{2}+m' ^{2}+2mm' cos \theta=1[/tex]

[tex]n^{2}+n' ^{2}+2nn' cos \theta=1[/tex]

[tex]mn+m'n'+(mn'+m'n)cos \theta =0[/tex],

then prove that [tex]m^{2}+n^{2}=cosec^{2} \theta[/tex]

3. The attempt at a solution

I have tri a lot but its difficult to eliminate m' or n'

If I add the first to equations and separate m^2+n^2 to left ide, again its difficult to prov the RHS to [tex]cosec ^{2} \theta[/tex]

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# Homework Help: Basic Trigonometry

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