Solve the following quadratic equations:
x2 – x + (1 + i) = 0
x2 – x + (1 + i) = 0
Given x2 – x + (1 + i) = 0
Recall that the roots of quadratic equation ax2 + bx + c = 0, where a ≠ 0, are given by
Here, a = 1, b = –1 and c = (1 + i)
By substituting –1 = i2 in the above equation, we get
We can write 3 + 4i = 4 – 1 + 4i
⇒ 3 + 4i = 4 + i2 + 4i [∵ i2 = –1]
⇒ 3 + 4i = 22 + i2 + 2(2)(i)
⇒ 3 + 4i = (2 + i)2 [∵ (a + b)2 = a2 + b2 + 2ab]
By using the result 3 + 4i = (2 + i)2, we get
[∵ i2 = –1]
∴ x = i or 1 – i
Thus, the roots of the given equation are i and 1 – i.