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If `x`is real, then the value of the expression `(x^2+14 x+9)/(x^2+2x+3)`lies between(a) 5 and 4 (b) 5 and `-4`(c) `-5a n d4`(d) none of theseA. [4, 5]B. [-4, 5]C. [-5, 4]D. none of these |
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Answer» Correct Answer - C `(x^(2)+14x+9)/(x^(2)+2x+3)=y` or ` x^(2)+14x+9=x^(2)y+2xy+3y` or ` x^(2)(y-1)+2x(y-7)+(3y-9)=0` Since x is real, we have `4(y-7)^(2)-4(3y-9)(y-1) ge 0` or ` 4(y^(2)+49-14y)-4(3y^(2)+9-12y) ge 0` or ` (y+5)(y-4) le 0` ` :. y in [-5,4]` |
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