TrigonometryHardSum, Difference, and Multiple-Angle Formulas ShareSum, Difference, and Multiple-Angle Formulas · Hard problemGiven sinθ=−513\sin\theta=-\tfrac{5}{13}sinθ=−135 with θ\thetaθ in Quadrant IV, find cosθ2\cos\dfrac{\theta}{2}cos2θ.A−52627-\dfrac{5\sqrt{26}}{27}−27526B−102626-\dfrac{10\sqrt{26}}{26}−261026C−52626-\dfrac{5\sqrt{26}}{26}−26526D−26526-\dfrac{26}{5\sqrt{26}}−52626Check Show answer Walk through it step by step Practice more like this Review this concept