The equation `x^2 - 3xy+ lambday^2 + 3x - 5y + 2 = 0` where `lambda` is a real number, represents a pair of straight lines. If `theta` is the angle between the lines, then `cosec^2theta =`A. 9B. 10C. 15D. 26

The equation `x^2 - 3xy+ lambday^2 + 3x - 5y + 2 = 0` where `lambda` i

1.	The equation `x^2 - 3xy+ lambday^2 + 3x - 5y + 2 = 0` where `lambda` is a real number, represents a pair of straight lines. If `theta` is the angle between the lines, then `cosec^2theta =`A. 9B. 10C. 15D. 26
Answer» Correct Answer - B The equation `x^(2)-3xy+lambda y^(2)+3x-5y+2=0` will represent a pair of straight lines, if `2lambda+2xx-(5)/(2)xx(3)/(2)xx-(3)/(2)-(-(5)/(2))^(2)-lambda((3)/(2))^(2)-2(-(3)/(2))^(2)=0` `rArr" "8 lambda+45-25-9lambda-18=0rArr lambda =2` Now, `tantheta=(2sqrt(h^(2)-ab))/(a+b)` `rArr" "tan theta=(2sqrt((9)/(4)-2))/(1+2)=(1)/(3)rArr" cosec"^(2)theta=1+9=10`

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