Question

One solution to a quadratic function, f, is given below.

√7 + 5i
Which of the following statements is true about the given function?

1) The other solution to function f is -√7 + 5i.
2) The other solution to function f is √7 - 5i.
3) Function f has no other solutions.
4) The other solution to function f is -√7 - 5i.

Answer 1

Answer: Another solution of function f is -5+7i

Explanation:

the conjugate of -5 -7i is -5+7i so another solution of function f is -5 + 7i

Answer 2

The correct option is (2)

For any quadratic equation: ax2 + bx + c = 0.

The complex roots are expressed in the form a ± bi.

where a is the real part
& b is the imaginary part.
Since, one root is √7 + 5i, therefore the other root will be of the form √7 - 5i.

Hence, option (2) is correct.