Ncert Solutions Chapter 4 Quadratic Equations Exercise 4.3 Q1 Download this solution
1. Find the roots of the following quadratic equations if they exist by the method of completing square.
(i)
(ii)
(iii)
(iv)
Solution (i)
First we divide equation by 2 to make coefficient of
equal to 1, we get
We divide middle term of the equation by
, we get
We add and subtract square of
from the equation
, we get
{
}
Taking Square root on both sides, we get
And
Therefore,
Solution (ii)
Dividing equation by 2, we get
Following procedure of completing square, we get
{
}
Taking square root on both sides, we get
And,
Therefore,
Solution (iii)
Dividing equation by 4 to make coefficient of
equal to 1, we get
Following the procedure of completing square, we get
{
}
Taking square root on both sides, we get
Quadratic equation has two roots. Here, both the roots have equal value. Therefore, value of
Solution (iv)
Dividing equation by 2 to make coefficient of
equal to 1.
Following the procedure of completing square, we get
{
}
Taking square root on both sides, right hand side does not exist because square root of negative number does not exist.
Therefore, there is no solution for quadratic equation
Faheem says
Correct ans
Gads Jolie says
Nice help…thnx