Find the roots of the equation below 7x2+1=0

Question

asked May 28, 2019 59.3k views

2 Answers

Alexey Popov · Answer 1 · 2019-06-02T13:54:05+0000

Answer:

The roots of the equation is:
$x=\pm i(√(7))/(7)$

Explanation:

Consider the provided equation.

7x^2+1=0

Subtract 1 from both the sides.

7x^2+1-1=-1

7x^2=-1

Isolate the variable by dividing both the side by 7.

(7x^2)/(7)=(-1)/(7)

x^2=(-1)/(7)

Take the square root:

$x=\pm \sqrt{(-1)/(7)}$

$x=\pm (1)/(√(7))i$

Now we multiply the numerator and the denominator by √7:

$x=\pm (1)/(√(7))* (√(7))/(√(7))i$

$x=\pm (√(7))/(7)i$

$x=\pm i(√(7))/(7)$

Hence, the roots of the equation is:
$x=\pm i(√(7))/(7)$