Question 1064117
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If x/a cos theta= y/b sin theta and ax/cos theta - by/ sin theta =a^2 – b^2 show that x^2/a^2 +y^2/b^2 =1
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From  {{{(x/a)*cos(theta)}}} = {{{(y/b)*sin(theta)}}} express 

{{{cos(theta)}}} =  {{{(((y/b))/((x/a)))*sin(theta)}}} = {{{((y*a)/(x*b))*sin(theta)}}} and substitute it into the second equality.
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