11 | ||
Jeżeli a ≥ | b, udowodnij prawdziwość nierówności | |
5 |
1 | 17 | 11 | ||||
x3− | x2− | x− | =0 | |||
5 | 5 | 5 |
1 | 1 | 1 | 1 | |||||
(x− | )3=x3−3x2( | )+3( | )x− | |||||
15 | 15 | 225 | 3375 |
1 | 1 | 1 | 1 | |||||
(x− | )3=x3− | x2+ | x− | |||||
15 | 5 | 75 | 3375 |
1 | 256 | 1 | ||||
(x− | )3− | (x− | )= | |||
15 | 75 | 15 |
1 | 1 | 1 | ||||
x3− | x2+ | x− | ||||
5 | 75 | 3375 |
256 | 256 | |||
− | x+ | |||
75 | 1125 |
1 | 256 | 1 | 1 | 17 | 767 | |||||||
(x− | )3− | (x− | )= x3− | x2− | x+ | |||||||
15 | 75 | 15 | 5 | 5 | 3375 |
−7425−767 | |
3375 |
1 | 256 | 1 | 8192 | 1 | 17 | 767 | ||||||||
(x− | )3− | (x− | )− | =x3− | x2− | x+ | ||||||||
15 | 75 | 15 | 3375 | 5 | 5 | 3375 |
8192 | ||
− | ||
3375 |
1 | 256 | 1 | 8192 | 1 | 17 | 11 | ||||||||
(x− | )3− | (x− | )− | =x3− | x2− | x− | ||||||||
15 | 75 | 15 | 3375 | 5 | 5 | 5 |
1 | ||
y = x− | ||
15 |
256 | 8192 | |||
y3− | y− | =0 | ||
75 | 3375 |
256 | 8192 | |||
(u+v)3− | (u+v)− | =0 | ||
75 | 3375 |
256 | 8192 | |||
u3+3u2v+3uv2+v3− | (u+v)− | =0 | ||
75 | 3375 |
8192 | 256 | |||
u3+v3− | +3(u+v)(uv− | )=0 | ||
3375 | 225 |
8192 | ||
u3+v3− | =0 | |
3375 |
256 | ||
3(u+v)(uv− | )=0 | |
225 |
8192 | ||
u3+v3= | ||
3375 |
256 | ||
uv= | ||
225 |
8192 | ||
u3+v3= | ||
3375 |
16777216 | ||
u3v3= | ||
11390625 |
8192 | 16777216 | |||
t2− | t+ | =0 | ||
3375 | 11390625 |
4096 | ||
(t− | )2=0 | |
3375 |
4096 | ||
u3= | ||
3375 |
4096 | ||
v3= | ||
3375 |
16 | ||
u= | ||
15 |
16 | ||
v= | ||
15 |
32 | ||
y= | ||
15 |
1 | 32 | |||
x− | = | |||
15 | 15 |
11 | ||
x = | ||
5 |
11 | ||
x=−1 ∨ x = | ||
5 |