Q. If cosA=6160 and tanB=158 and angles A and B are in Quadrant I, find the value of tan(A+B).Answer:
Use tangent identity: Use the identity for the tangent of a sum of two angles.The identity is tan(A+B)=1−tanA⋅tanBtanA+tanB.We know tanB, but we need to find tanA.
Find tanA: Find tanA using the given value of cosA and the Pythagorean identity.Since cosA=hypotenuseadjacent, we have adjacent=60 and hypotenuse=61.To find the opposite side, we use the Pythagorean theorem: opposite2=hypotenuse2−adjacent2.
Calculate opposite side: Calculate the opposite side for angle A. opposite2=612−602=3721−3600=121. Taking the square root gives us opposite=11.
Calculate tanA: Calculate tanA using the opposite and adjacent sides.tanA=adjacentopposite=6011.
Substitute into identity: Substitute tanA and tanB into the identity for tan(A+B).\(\tan(A+B) = \frac{\tan A + \tan B}{1 - \tan A \cdot \tan B} = \frac{\frac{11}{60} + \frac{8}{15}}{1 - (\frac{11}{60} \cdot \frac{8}{15}))\).
Simplify expression: Simplify the expression for \(\tan(A+B)\). First, find a common denominator for the sum in the numerator: \(60 \times 15 = 900\). \(\tan(A+B) = \frac{(11 \times 15) + (8 \times 60)}{900 - (11 \times 8)} = \frac{(165 + 480)}{(900 - 88)}\).
Reduce fraction: Continue simplifying the expression. \(\tan(A+B) = \frac{645}{900 - 88} = \frac{645}{812}\). Reduce the fraction to its simplest form if possible. The fraction \(\frac{645}{812}\) cannot be simplified further as they do not have common factors other than \(1\).