Question 1104763
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If the angle is in quadrant 1 and sin(theta)=21/29, then cos(theta) = 20/29:
{{{sinx^2+cosx^2 = 1}}}
{{{441/841+cosx^2 = 1}}}
{{{cosx^2 = 400/841}}}
{{{cosx = 2.0/29}}}<br>
Then tan(theta) is {{{(21/29)/(20/29) = 21/20}}}<br>
Beyond that I can't help you, because I can't tell whether "tan2(theta)" means {{{tan(2*theta)}}} or {{{(tan(theta))^2}}}