(2+i)(2-1)=0

Solution for (2+i)(2-1)=0 equation:

Simplifying
(2 + i)(2 + -1) = 0

Combine like terms: 2 + -1 = 1
(2 + i)(1) = 0

Reorder the terms for easier multiplication:
1(2 + i) = 0
(2 * 1 + i * 1) = 0
(2 + 1i) = 0

Solving
2 + 1i = 0

Solving for variable 'i'.

Move all terms containing i to the left, all other terms to the right.

Add '-2' to each side of the equation.
2 + -2 + 1i = 0 + -2

Combine like terms: 2 + -2 = 0
0 + 1i = 0 + -2
1i = 0 + -2

Combine like terms: 0 + -2 = -2
1i = -2

Divide each side by '1'.
i = -2

Simplifying
i = -2