Să se efectueze calculele:
a) (4x - 3)²-(3x + 2)² - 7x(x - 1);
b) (3x + 4)² - 5(x - 3)² - 4x(x + 3);
c) 2(x + 5)² - 4(x − 2)(x + 2) + 2x(x − 3);
d) 2(x + 5)² - 3(x - 1) + x(x + 6);
e) 4(x + 2) - 3(2x - 1)(2x + 1) - 2x(x + 3);
f); (4x - 3)² - 4(2x + 5)(2x - 5) + 3(4x - 1);
g) (5x-3)²-6(2x + 3)(2x - 3) − x(x + 1);
h) (3x-4)²-(3x + 2)(3x - 2) + 3(4x + 3),
nu este de liceu este de gimnaziu dar va rog sa ma ajutați
Răspunsuri la întrebare
a) (4x - 3)²- (3x + 2)² - 7x(x - 1) =
= (4x)² - 2 * 4x * 3 + 3² - [(3x)² + 2 * 3x * 2 + 2²] - 7x² + 7x =
= 16x² - 24x + 9 - (9x² + 12x + 4) - 7x² + 7x =
= 16x² - 24x + 9 - 9x² - 12x - 4 - 7x² + 7x =
= 5 - 29x
b) (3x + 4)² - 5(x - 3)² - 4x(x + 3) =
= (3x)² + 2 * 3x * 4 + 4² - 5(x² - 2 * x * 3 + 3²) - 4x² - 12x =
= 9x² + 24x + 16 - 5(x² - 6x + 9) - 4x² - 12x =
= 9x² + 24x + 16 - 5x² + 30x - 45 - 4x² - 12x =
= 42x - 29
c) 2(x + 5)² - 4(x − 2)(x + 2) + 2x(x − 3) =
= 2(x² + 2 * x * 5 + 5²) - 4(x² - 2²) + 2x² - 6x =
= 2(x² + 10x + 25) - 4(x² - 4) + 2x² - 6x =
= 2x² + 20x + 50 - 4x² + 16 + 2x² - 6x =
= 14x + 66
= 2(7x + 33)
d) 2(x + 5)² - 3(x - 1) + x(x + 6) =
= 2(x² + 2 * x * 5 + 5²) - 3x + 3 + x² + 6x =
= 2(x² + 10x + 25) - 3x + 3 + x² + 6x =
= 2x² + 20x + 50 - 3x + 3 + x² + 6x =
= 3x² + 23x + 53
e) 4(x + 2) - 3(2x - 1)(2x + 1) - 2x(x + 3) =
= 4x + 8 - 3[(2x)² - 1²] - 2x² - 6x =
= 4x + 8 - 3(4x² - 1) - 2x² - 6x =
= 4x + 8 - 12x² + 3 - 2x² - 6x =
= - 14x² - 2x + 11
f) (4x - 3)² - 4(2x + 5)(2x - 5) + 3(4x - 1) =
= (4x)² - 2 * 4x * 3 + 3² - 4[(2x²) - 5²] + 12x - 3 =
= 16x² - 24x + 9 - 4(4x² - 25) + 12x - 3 =
= 16x² - 24x + 9 - 16x² + 100 + 12x - 3 =
= - 12x + 106
g) (5x - 3)²- 6(2x + 3)(2x - 3) − x(x + 1) =
= (5x)² - 2 * 5x * 3 + 3² - 6[(2x)² - 3²] - x² - x =
= 25x² - 30x + 9 - 6(4x² - 9) - x² - x =
= 25x² - 30x + 9 - 24x² + 54 - x² - x =
= - 31x + 63
h) (3x - 4)²- (3x + 2)(3x - 2) + 3(4x + 3) =
= (3x)² - 2 * 3x * 4 + 4² - [(3x)² - 2²] + 12x + 9 =
= 9x² - 24x + 16 - (9x² - 4) + 12x + 9 =
= 9x² - 24x + 16 - 9x² + 4 + 12x + 9 =
= - 12x + 29
* Sper că te-am ajutat! *