

InterviewSolution
Saved Bookmarks
1. |
If `"sin"(alpha + beta) "sin" (alpha-beta) = "sin" gamma(2"sin" beta + "sin"gamma) " where " 0 lt alpha, beta, lt pi,` then the straight line whose equation is `x "sin" alpha+y "sin" beta-"sin" gamma = 0` passes through the pointA. (1,1)B. (-1,1)C. (1,-1)D. none of these |
Answer» Correct Answer - C `"sin"(alpha+beta)"sin"(alpha-beta)="sin" gamma(2"sin"beta + "sin"gamma)` `"or ""sin"^(2)alpha-("sin"beta + "sin" gamma)^(2)=0` `"or "("sin"alpha+"sin" beta+"sin"gamma)("sin"alpha-"sin"beta-"sin"gamma)=0` `"Since " 0 lt alpha, beta, gamma lt pi," we have"` `"sin"alpha+"sin"beta+"sin"gamma ne 0` `therefore " sin"alpha-"sin"beta-"sin"gamma = 0` `"So, "x"sin" alpha+y"sin" beta-"sin"gamma=0` passes through the fixed point (1,-1). |
|