BTVN:
1. Tim
Tìm x, biết:
a) (3x-2)² + (5-2x)²
= 29
(b) 27x3 - 27x² + 9x ==
- 1 = 0
10
c) x² - 10x + 25 = 315-x)
d) (x+2)3
3
-
3
(x-2) 3-6 (2x-1)²
= 10.
e) x³- 15x² + 75x - 125
K) 27 - 27x + 9x² - x
3
= 64
= 9x (x
-
3)
9) (2x-5)² + (3-x)² = Sx² - 7
+) (7x³ +5-9x) (7x³ + 9x+5) - (+x² + ...
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