Use a Double-Angle Formula to Find the Exact Value of Cos2u

question 11

Multiple Choice

Use a double-angle formula to find the exact value of cos2u when​ $$\sin u = \frac { 7 } { 25 } \text {, where } \frac { \pi } { 2 } < u < \pi$$

• A) \(\cos 2 u = \frac { 527 } { 625 }\)
• B)​ \(\cos 2 u = - \frac { 1152 } { 625 }\)
• C)​ \(\cos 2 u = \frac { 336 } { 625 }\)
• D)​ \(\cos 2 u = \frac { 168 } { 625 }\)
• E)​ \(\cos 2 u = - \frac { 478 } { 625 }\)

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Labia Majora

The outer folds of skin surrounding the vulva in females, serving protective and sexual functions.

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The physiological and emotional state of arousal and anticipation that precedes sexual activity, characterized by increased heart rate, blood flow, and libido.

Hardening

The process of becoming firm or rigid; in a medical context, it can refer to the calcification or other physical changes in tissues or vessels.