C-09-Q084mediumsingle_mcqIn the same triangle, cosθ=?\cos\theta = ?cosθ=?a1213\dfrac{12}{13}1312b513\dfrac{5}{13}135c512\dfrac{5}{12}125d135\dfrac{13}{5}513ব্যাখ্যাFor θ=∠ABC\theta = \angle ABCθ=∠ABC, the adjacent side is BC=12BC = 12BC=12 and the hypotenuse is AB=13AB = 13AB=13. Therefore cosθ=adjhyp=1213\cos\theta = \dfrac{\text{adj}}{\text{hyp}} = \dfrac{12}{13}cosθ=hypadj=1312.