3*6=18 cm²

3²-2²=5

Wurzel 5 = 2,24

2 / 2,24 = 0,89

tan^-1 (0,89) = 41,67°

90°-41,67°=48,33

3*3*3,14*48,33°/360°= 3,79 cm²

18 cm²+3,79cm²= 21,79 cm²

(x−1)⋅(x−2)−(x−3)²

x²-2x-x+6-(x²-6x+9)

x²-3x+6-x²+6x-9

3x-3

3x=3

x=1

(x-1)(x-2)-(x-3)2

(x²-2x-x+2)-(2x-6)

x²-3x+2-2x+6

x²-5x+8