z | ||
Mam za zadanie narysować zbiór re | = 2. z ≠ −i | |
z + i |
z | x + iy | x + iy | |||
= | = | ||||
z + i | x + iy + i | x + (y + 1)i |
z | x+iy | x+iy | (x+iy)(x−i(y+1)) | ||||
= | = | = | = | ||||
z+i | x+iy+i | x+i(y+1) | (x+i(y+1)(x−i(y+1)) |
x2−ix(y+1)+ixy−i2y(y+1) | x2−ixy−ix+ixy+y2+y | |||
= | = | = | ||
x2−i2(y+1)2 | x2+(y+1)2 |
x2+y2+y−ix | x2+y2+y | x | ||||
= | = | −i* | ||||
x2+(y+1)2 | x2+(y+1)2 | x2+(y+1)2 |
z | x2+y2+y | |||
I stąd Re( | )= | |||
z+i | x2+(y+1)2 |
x2+y2+y | |
=2 | |
x2+(y+1)2 |
3 | 1 | |||
x2+(y+ | )2= | |||
2 | 4 |
3 | 1 | |||
Jest to okrąg o środku w punkcie (0,− | ) i promieniu równym r= | . | ||
2 | 2 |