Math help

<p>Can somone show me how to do this problem?
Thanks in advance!</p>

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<p>I just substituted numbers for the angles and found that the answer is 1. It said that all three sides are of different lengths, so the angles must all be of different lengths too. Because it does not specify a value for any angle or side, the expression must be true for any two complementary A and B angles. I just did a 30-60-90 triangle, because it is a right triangle. sin of 60 is equal to .866 or square root of 3 over two. Square the square root of 3 over 2 and you get the 3/4 or .75. Then take the sin of 30 which is .5 or 1/2. Square that and you get .25. .75 + .25 = 1. I hope I'm right and that this helps.</p>

<p>ok thanks!!</p>

<p>sin^2 A + cos^2 A = 1 by trigonometric laws.
cos A = sin b because A+B = 90 degrees.
Therefore sin^2 A + sin^2 B = 1</p>

<p>also it would simply (a/c)^2 +(b/c)^2 which is ( a^2 + b^2)/c^2 according to Pythagorean its simply (c^2/c^2) which is one. </p>

<p>Substituting can be bad idea since it isn't always reliable.</p>