English

`X^2-4x+1=0` - Mathematics

Advertisements
Advertisements

Question

`x^2-4x+1=0`

Advertisements

Solution

`x^2-4x+1=0` 

⇒`x^2-4x=1` 

⇒`x^2-2xx x xx2+2^2=-1+2^2`          (Adding `2^2`on both sides)

⇒`(x-2)^2=+-sqrt3` 

⇒`x-2=+-sqrt3`                    (Taking square root on the both sides)

⇒`x-2=sqrt3  or  x-2=-sqrt3` 

⇒`x=2+sqrt3  or  x=2-sqrt3` 

Hence, `2+sqrt3 and 2-sqrt3`  are the roots of the given equation.

 

shaalaa.com
  Is there an error in this question or solution?
Chapter 10: Quadratic Equations - Exercises 2

APPEARS IN

R.S. Aggarwal Mathematics [English] Class 10
Chapter 10 Quadratic Equations
Exercises 2 | Q 2

RELATED QUESTIONS

Solve the following quadratic equation for x:

`x^2+(a/(a+b)+(a+b)/a)x+1=0`


Find the roots of the following quadratic equation by factorisation:

x2 – 3x – 10 = 0


Find the consecutive numbers whose squares have the sum 85.


The area of a right angled triangle is 165 m2. Determine its base and altitude if the latter exceeds the former by 7 m.


Solve the following quadratic equations by factorization:

\[3\left( \frac{7x + 1}{5x - 3} \right) - 4\left( \frac{5x - 3}{7x + 1} \right) = 11; x \neq \frac{3}{5}, - \frac{1}{7}\]


If 1 is a root of the quadratic equation \[3 x^2 + ax - 2 = 0\] and the quadratic equation \[a( x^2 + 6x) - b = 0\] has equal roots, find the value of b.


Find the value of p for which the quadratic equation 

\[\left( p + 1 \right) x^2 - 6(p + 1)x + 3(p + 9) = 0, p \neq - 1\] has equal roots. Hence, find the roots of the equation.

Disclaimer: There is a misprinting in the given question. In the question 'q' is printed instead of 9.


If the equation x2 + 4x + k = 0 has real and distinct roots, then


If ax2 + bx + c = 0 has equal roots, then c =


The number of quadratic equations having real roots and which do not change by squaring their roots is


Solve the following equation:  abx2 +(b2-ac) x - bc = 0


Solve the following equation :

`("x" - 1)/("x" - 2) + ("x" - 3)/("x" - 4) = 3  1/3`


If an integer is added to its square the sum is 90. Find the integer with the help of a quadratic equation.


Solve the equation 2x `-(1)/x` = 7. Write your answer correct to two decimal places.


Solve the following equation by factorization

6p2+ 11p – 10 = 0


Solve the following equation by factorization.

a2x2 + 2ax + 1 = 0, a ≠ 0


The hypotenuse of grassy land in the shape of a right triangle is 1 metre more than twice the shortest side. If the third side is 7 metres more than the shortest side, find the sides of the grassy land.


Paul is x years old and his father’s age is twice the square of Paul’s age. Ten years hence, the father’s age will be four times Paul’s age. Find their present ages.


In the centre of a rectangular lawn of dimensions 50 m × 40 m, a rectangular pond has to be constructed so that the area of the grass surrounding the pond would be 1184 m2 [see figure]. Find the length and breadth of the pond.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×