Which of the following is a solution of x2 + 4x + 10?
2 + i times the square root of 6
-2 + i times the square root of 24
-2 + i times the square root of 6
2 + i times the square root of 24
Solution:
The equation x2 + 4x + 10 is a quadratic equation the general form of which is a2 + bx + c.
The roots of the equation a2 + bx + c are:
(-b ± √b2 - 4ac)/2a
For the equation x2 + 4x + 10
Here a = 1, b = 4, c = 1
Hence the value of
b2 - 4a = (4)2 - 4 × 1 × 10 = 16 - 40 = - 24
Therefore
√b2 - 4ac = √-24 = √-4 × 6 = 2 × √6 × √-1 = i2√6 where i = √-1
The solution or roots of the equation are -4/2 ± 2i√6/2
i.e. -2 + i√6 and -2 - i√6
Which of the following is a solution of x2 + 4x + 10?
Summary:
The solution or roots of the equation are -2 ± i√6 i.e. -2 + i√6 and -2 - i√6,-2 + i times the square root of 6 is the correct option.
Math worksheets and
visual curriculum
visual curriculum