Given: sin theta = 2/5. This tells us that the lengths of the opp side and the hyp are 2 and 5 respectively. The adj side is found using the Pyth. Thm.: 5^2-2^2= 25-4 = 21, so that the adj side is sqrt(21).
The double angle formula for the sine is sin 2theta = 2 sin theta *cos theta.
In this particular problem, the sine of 2theta is 2*(2/5)*[sqrt(21) / 5], or:
(4/25)*sqrt(21).
Hope this helps you out.... 85x + 26y <span>
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1. 5/6
2. 2/3 x 5/6
3. 2/3 x 5/6 = 10/18
Multiply the numerators— 2 x 5 = 10
Multiply the denominators—3x 6= 18
4. 10/18 = 5/9
Find the greatest common factor of 10 and 18 which is 2.
Divide the numerator by 2– 10/2 = 5
Divide the denominator by 2– 18/2 = 9
I hope this helps!
