Solve for x, $2{x^2} - x = 0$
Answer
627k+ views
Hint:Check for the highest power of the variable. The highest power determines the number of solutions for the equation. In this case, the highest power is 2 and hence you’ll get 2 solutions for the quadratic equation.
Complete step by step solution:
The given equation has a highest power of 2 on variable “x” and thus revealing that the equation will give us 2 solutions.
The standard quadratic equation looks like,
$a{x^2} + bx + c = 0$
Comparing the standard equation to that of the question, we see that
a = 2, b = -1 and c = 0.
Thus, we can rewrite the equation in the question as,
$2{x^2} - x + 0 = 0$
If we check the question for “Mid-term factorization”, we see that it is not possible.
We take an easier approach.
$2{x^2} - x = 0$
$ \Rightarrow 2{x^2} = x$…… (Taking x from LHS to RHS)
\[ \Rightarrow \dfrac{{2{x^2}}}{x} = \dfrac{x}{x}\]…… (Dividing throughout by x)
$ \Rightarrow 2x = 1$
$ \Rightarrow \dfrac{{2x}}{2} = \dfrac{1}{2}$……. (Dividing throughout by 2)
$ \Rightarrow x = \dfrac{1}{2}$
This above method gives us only one value of x. But we know that there are2 values that are to be found.
If we take the following approach, 2 values are found.
$2{x^2} - x = 0$
$ \Rightarrow (2x - 1)x = 0$
This means that x=0 or $(2x - 1) = 0$
$ \Rightarrow x = 0\;or\;x = \dfrac{1}{2}$
Note: Incase of imaginary values, this method is very cumbersome and hence should not be used. In such a case, you can use the formula, $x = \dfrac{{ - b \pm \sqrt {{b^2} - 4ac} }}{{2a}}$to find the factors. This formula can be used for any kind of quadratic equation arranged as per the standard quadratic equation. It reduces the time required to solve more complex equations.
Complete step by step solution:
The given equation has a highest power of 2 on variable “x” and thus revealing that the equation will give us 2 solutions.
The standard quadratic equation looks like,
$a{x^2} + bx + c = 0$
Comparing the standard equation to that of the question, we see that
a = 2, b = -1 and c = 0.
Thus, we can rewrite the equation in the question as,
$2{x^2} - x + 0 = 0$
If we check the question for “Mid-term factorization”, we see that it is not possible.
We take an easier approach.
$2{x^2} - x = 0$
$ \Rightarrow 2{x^2} = x$…… (Taking x from LHS to RHS)
\[ \Rightarrow \dfrac{{2{x^2}}}{x} = \dfrac{x}{x}\]…… (Dividing throughout by x)
$ \Rightarrow 2x = 1$
$ \Rightarrow \dfrac{{2x}}{2} = \dfrac{1}{2}$……. (Dividing throughout by 2)
$ \Rightarrow x = \dfrac{1}{2}$
This above method gives us only one value of x. But we know that there are2 values that are to be found.
If we take the following approach, 2 values are found.
$2{x^2} - x = 0$
$ \Rightarrow (2x - 1)x = 0$
This means that x=0 or $(2x - 1) = 0$
$ \Rightarrow x = 0\;or\;x = \dfrac{1}{2}$
Note: Incase of imaginary values, this method is very cumbersome and hence should not be used. In such a case, you can use the formula, $x = \dfrac{{ - b \pm \sqrt {{b^2} - 4ac} }}{{2a}}$to find the factors. This formula can be used for any kind of quadratic equation arranged as per the standard quadratic equation. It reduces the time required to solve more complex equations.
Recently Updated Pages
Write structures of the following compounds i 2 Chloro3methylpentane class 11 chemistry CBSE

What is BLO What is the full form of BLO class 8 social science CBSE

Explain the Treaty of Vienna of 1815 class 10 social science CBSE

A Paragraph on Pollution in about 100-150 Words

XIX+XXX A 49 B 51 C 55 D 44 class 5 maths CBSE

If x a + bt + ct2 where x is in meters and t is in class 11 physics CBSE

Trending doubts
One Metric ton is equal to kg A 10000 B 1000 C 100 class 11 physics CBSE

Draw a diagram of nephron and explain its structur class 11 biology CBSE

10 examples of friction in our daily life

Proton was discovered by A Thomson B Rutherford C Chadwick class 11 chemistry CBSE

Bond order ofO2 O2+ O2 and O22 is in order A O2 langle class 11 chemistry CBSE

Draw a labelled diagram of the neuron and describe class 11 biology CBSE

