PLZ solve QA questions
Q1 In a triangle ABC the internal bisector of angle(A)meets BC at D. If AB=4, AC=3 and anlgle(A) = 60, then the length of AD is
Q2. If x, y and z are real numbers such that x + y + z =5 and xy + yz + zx = 3, what is the largest value that x can have ?
a. 5/3 b. radic19 c. 13/3 d. None
Q3. The number of real roots of the equation A2/x + B2/(x-1)=1 , where A and B are real numbers not equal to zero simultaneously is
a. None b. 1 c. 2 d. b or c
Q4. In how many ways is it possible to choose a white and a black square on a chessboard so that the squares must not lie in the same row or column ?
a. 56 b. 896 c. 60 d. 768
Given
A2/x + B2/(x-1) = 1
=> ( x - 1)A2+ x B2/x(x-1) = 1
=>( x - 1)A2+ x B2 = x(x-1)
Above is a quadrtic equation where x is the variable
so can have either 1 or 2 roots
answer d