1. 3x4 + 10x3 − 10x − 3 =
2. 4x4 − 13x2 + 3 =
3. x3 − 7x − 6 =
4. 4x3 − 7x + 3 =
5. x4 − 2x3 + 2x2 − 2x + 1 =
6. x4 + 4 =
7. x4 − x2 + 16 =
8. (x2 − 5)2 − 16 =
9. (x2 + 1)2 − 4x2 =
10. 36 − x2(x−5)2
11. (x2 − x − 1)2 − x4 =
12. (x3 + x2 − 1)2 − (2x2 − 3)2
?
może np. niektóre tak :
2. 4x4−13x2+3 = 4x4−12x2−x2+3 = 4x2(x2−3)−1(x2−3) = (x2−3)(4x2−1) =
= (x2−√32)(2x−1)(2x+1) =4(x−√3)(x+√3(x−1]{2})(x+u{12) ;
4. 4x3−7x+3 = 4x3−4x−3x+3 = 4x(x2−1)−3(x−1) = 4x(x−1)(x+1)−3(x−1) =
= (x−1)(4x2+4x−3) = (x−1)( i "delta w tym nawiasie) dokończ ... ;
5. x4−2x3+2x2−2x+1 = x4+2x2+1−2x3−2x = (x2+1)2−2x(x2+1) =
= (x2+1)(x2+1−2x) = (x2+1)(x2−2x+1) = (x2+1)(x−1)2 ;
6. x4+4 = x4+2*2x2+4−4x2 = (x2+2)2−(2x)2 = (x2+2−2x)(x2+2+2x) =
= (x2−2x+2)(x2+2x+2) ;
no i ostatni np.
12 (x3+x2−1)2−(2x2−3)2 = (x3+x2−1−2x2+3)(x3+x2−1+2x2−3) =
= (x3−x2+2)(x3+3x2−4) = (x3+1−x2+1)(x3−1+3x2−3) =
= [(x+1)(x2−x+1)−(x−1)(x+1)] [(x−1)(x2+x+1)+3(x−1)(x+1)] =
= (x+1)(x2−x+1−x+1)(x−1)(x2+x+1+3x+3) = (x+1)(x−1)(x2−2x+2)(x2+4x+4) =
= (x+1)(x−1)(x+2)2(x2−2x+2) . ... ufff
| 1 | ||
=(x2−1)[3(x2+1)+10x]=(x−1)(x+1)(3x2+10x+3)=3(x−1)(x+1)(x+3)(x+ | ) | |
| 3 |
| 1 | ||
Δ=64, √Δ=8, x1=−3, x2=− | ||
| 3 |
| 1 | 1 | |||
2. 4x4 − 13x2 + 3 =(podst. t=x2)=4t2−13t+3=4(t− | )(t−3)=4(x2− | )(x2−3)= | ||
| 4 | 4 |
| 1 | 1 | |||
=4(x− | )(x+ | )(x−√3)(x+√3) | ||
| 2 | 2 |
| 1 | ||
Δ=121, √Δ=11, t1= | , t2=3 | |
| 4 |