Advertisements
Advertisements
Question
Which constant must be added and subtracted to solve the quadratic equation `9x^2 + 3/4x - sqrt(2) = 0` by the method of completing the square?
Options
`1/8`
`1/64`
`1/4`
`9/64`
Solution
`bb(1/64)`
Explanation:
Given equation is `9x^2 + 3/4x - sqrt(2)` = 0
`(3x)^2 + 1/4 (3x) - sqrt(2)` = 0
On putting 3x = y,
We have `y^2 + 1/4y - sqrt(2)` = 0
`y^2 + 1/4y + (1/8)^2 - (1/8)^2 - sqrt(2)` = 0
`(y + 1/8)^2 = 1/64 + sqrt(2)`
`(y + 1/8)^2 = (1 + 64 sqrt(2))/64`
Thus, `1/64` must be added and subtracted to solve the given equation.
APPEARS IN
RELATED QUESTIONS
For what value of m, are the roots of the equation (3m + 1)x2 + (11 + m) x + 9 = 0 equal?
Determine the nature of the roots of the following quadratic equation:
2(a2 + b2)x2 + 2(a + b)x + 1 = 0
Find the values of k for which the roots are real and equal in each of the following equation:
x2 - 4kx + k = 0
Determine the nature of the roots of the following quadratic equation :
4x2 - 8x + 5 = 0
Solve the following quadratic equation using formula method only
x2 - 4x - 1 = 0
Find the values of k so that the sum of tire roots of the quadratic equation is equal to the product of the roots in each of the following:
kx2 + 2x + 3k = 0
Find the values of k for which each of the following quadratic equation has equal roots: x2 – 2kx + 7k – 12 = 0 Also, find the roots for those values of k in each case.
State whether the following quadratic equation have two distinct real roots. Justify your answer.
3x2 – 4x + 1 = 0
Solve the following quadratic equation:
x2 + 4x – 8 = 0
Give your Solution correct to one decimal place.
(Use mathematical tables if necessary.)
The roots of the quadratic equation x2 – 6x – 7 = 0 are ______.