Question 1018459
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If sin(θ)= 4/7 and tan(θ)>0, find cos(θ)
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{{{cos(theta)}}} = {{{sqrt(1-sin^2(theta))}}} = {{{sqrt(1 - (4/7)^2)}}} = {{{sqrt(1 - 16/49)}}} = {{{sqrt((49-16)/49)}}} = {{{sqrt(33/49)}}} = {{{sqrt(33)/7}}}.


The sign of the square root is chosen "+" since {{{sin(theta)}}} > 0 and {{{tan(theta)}}} > 0.
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