Sail E0 Webinar
Question


A and B solved a quadratic equation. In solving it , A made a mistake in the constant term and obtained the roots as 5, -3 while B made a mistake in the coefficient  of x and obtained the roots as 1, -3. The correct roots of the equation are


Options:
A .   1,3
B .   -1,3
C .   -1,-3
D .   1,-1
E .   33128
Answer: Option B
:
B

Using the reverse gear approach
If the equation is ax2+bx+c=0.
A's mistake will be in "c”, hence sum of roots = ba=2.....(i) will be the correct value. Product of roots = ca will be wrong in this case
B's mistake will be in "b”, hence product of roots =ca=3......(ii) will yield the correct value. In this case, sum of roots value = ba will be wrong


Look in the answer options for the pair of roots which satisfy sum of roots = 2 and product of roots = -3. Answer is option (b).



Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published. Required fields are marked *

More Questions on This Topic :


Latest Videos

Latest Test Papers