Question 1099165
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sin(75) = sin(45+30) = sin(45)*cos(30) + cos(45)*sin(30) = {{{(sqrt(2)/2)*(sqrt(3)/2) + (sqrt(2)/2)*(1/2)}}} = {{{sqrt(6)/4 + sqrt(2)/4}}}.



Your answer is CORRECT !


But, probably, the computer system is not so smart as it should be.


Also try  to input  {{{sqrt(6)/4 + sqrt(2)/4}}}  and  {{{sqrt(2)/4 + sqrt(6)/4}}}  or other equivalent forms.
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