Step by step...shows how to get -22/7
<span>If we are to compare which among the given fractions is smaller, we first determine the decimal equivalent of each. If we are to solve for those, we determine that 3/4 is equal to 0.75 and 1/4 is equal to 0.25. This is done by dividing the numerator by the denominator. Comparing 0.75 and 0.25, we can conclude that 0.75 or 3/4 is greater compared to 0.25 or 1/4. </span>
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).
