You can put this solution on YOUR website! if a*sin^2 + b*cos^2 = c
then prove that: tan = sqrt((c-b)/(a-c))
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a*sin^2 + b*cos^2 = c
a*sin^2 + a*cos^2 + (b-a)*cos^2 = c
a + (b-a)*cos^2 = c
cos^2 = (a-c)/(a-b)
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a*sin^2 + b*cos^2 = c
a*sin^2 - b*sin^2 + b*cos^2 + b*sin^2 = c
sin^2*(a-b) + b = c
sin^2 = (c-b)/(a-b)
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tan^2 = sin^2/cos^2
tan^2 = ((c-b)/(a-b))/((a-c)/(a-b))
tan^2 = (c-b)/(a-c)
tan =