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anonymous
 5 years ago
what is the exact value of sin15 ? (using the subtraction formula)
anonymous
 5 years ago
what is the exact value of sin15 ? (using the subtraction formula)

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't know about the subtraction formula (never heard of it) but the half angle identity should work

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[\sin^215=\frac{1\cos 30}{2}=\frac{1\sqrt{3}/2}{2}=\frac{2\sqrt{3}}{4}\] \[\sin15=\frac{\sqrt{2\sqrt{3}}}{2}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0That's it right there^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I think the subtraction formula would mean that you would take two sin values that you know and use them to get sin 15 Sin 45  Sin 30 I will get back with the formula

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0OK here is the formula sin(A−B) = sin A cos B − cos A sin B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im required to use this formula sin(st)= sin(s)cos(t)  cos(s)sin(t)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sin(4530) = sin45*cos30  cos45*sin30

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sin 45 = sqrt2/2 cos 45 = sqrt2/2 sin 30 = 1/2 cos 30 = sqrt3/2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The difference identity! Yup that works better!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sqrt2/2*sqrt3/2  sqrt2/2*1/2 sqrt6/2  sqrt2/2 (sqrt6  sqrt2) /2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0would it be over 4 after multiplying
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