Select the answer which is equivalent to the given expression using your calculator. sin A=(55)/(73) and A is in Quadrant I. Find cos 2A. (2640)/(5329) (5280)/(5329) (-721)/(5329) (-1442)/(5329)

Question

Select the answer which is equivalent to the given expression using your calculator.  sin A=(55)/(73) and  A is in Quadrant I. Find  cos 2A.  (2640)/(5329)  (5280)/(5329)  (-721)/(5329)  (-1442)/(5329)

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Given information: We are given that sin A = 55/73 and A is in Quadrant I. We need to find cos 2A. We can use the double angle formula for cosine, which is cos 2A = cos^2 A - sin^2 A or cos 2A = 2cos^2 A - 1. Since we have the value of sin A, we can find cos A using the Pythagorean identity sin^2 A + cos^2 A = 1.Find cos A: First, let's find cos A. We know that sin^2 A + cos^2 A = 1. So, cos^2 A = 1 - sin^2 A. We plug in the value of sin A to find cos^2 A. cos^2 A = 1 - (55/73)^2Calculate sin^2 A: Calculate (55/73)^2 to find sin^2 A. (55/73)^2 = 3025/5329Subtract sin^2 A: Subtract sin^2 A from 1 to find cos^2 A. cos^2 A = 1 - 3025/5329 cos^2 A = (5329/5329) - (3025/5329) cos^2 A = 2304/5329Use double angle formula: Now we have cos^2 A, we can use the double angle formula for cosine. We choose cos 2A = 2cos^2 A - 1 because it directly uses cos^2 A. cos 2A = 2(2304/5329) - 1Calculate 2(2304/5329): Calculate 2(2304/5329). 2(2304/5329) = 4608/5329Subtract 1: Subtract 1 from 4608/5329 to find cos 2A. cos 2A = 4608/5329 - 5329/5329 cos 2A = (4608 - 5329)/5329 cos 2A = -721/5329

Select the answer which is equivalent to the given expression using your calculator. $\sin A=\frac{55}{73}$ and $\mathrm{A}$ is in Quadrant I. $\newline$ Find $\cos 2 A$ . $\newline$ $\frac{2640}{5329}$ $\newline$ $\frac{5280}{5329}$ $\newline$ $\frac{-721}{5329}$ $\newline$ $\frac{-1442}{5329}$

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