Bài 1 : Phân tích đa thức thành nhân tử :a) X^2 – 5x +6 b ) 3x^2 + 9x – 30 c) x^2 – 3x + 2d)X^2 – 9x + 18 e) x^2 -6x + 8 f) x^2 -5x -14g) x^2 + 6x +5 h) x^2 – 7x +12 i) x^2 – 7x+ 10Bài 2 :a) 3x^2 – 5x 2 b) 2x^2 + x -6c) 7x^2 + 50x +7d) 12x^2 +7 – 12e) 15x^2 + 7x-2f) A^2 -5a – 14g) 2m^2 + 10m + 8h) 4p^2 – 36p + 56i) 2x^2 + 5x +...
Đọc tiếp
Bài 1 : Phân tích đa thức thành nhân tử :
a) X^2 – 5x +6 b ) 3x^2 + 9x – 30 c) x^2 – 3x + 2
d)X^2 – 9x + 18 e) x^2 -6x + 8 f) x^2 -5x -14
g) x^2 + 6x +5 h) x^2 – 7x +12 i) x^2 – 7x+ 10
Bài 2 :
a) 3x^2 – 5x 2
b) 2x^2 + x -6
c) 7x^2 + 50x +7
d) 12x^2 +7 – 12
e) 15x^2 + 7x-2
f) A^2 -5a – 14
g) 2m^2 + 10m + 8
h) 4p^2 – 36p + 56
i) 2x^2 + 5x + 2
Bài 1: a) x2 - 5x + 6 = x2 - 2x - 3x + 6 = x(x - 2) - 3(x - 2) = (x - 3)(x - 2)
b) 3x2 + 9x - 30 = 3x2 + 15x - 6x - 30 = 3x(x + 5) - 6(x + 5) = (3x - 6)(x + 5) = 2(x - 2)(x + 5)
c) x2 - 3x + 2 = x2 - 2x - x + 2 = x(x - 2) - (x - 2) = (x - 1)(x - 2)
d) x2 - 9x + 18 = x2 - 3x - 6x + 18 = x(x - 3) - 6(x - 3) = (x - 6)(x - 3)
e) x2 - 6x + 8 = x2 - 2x - 4x + 8 = x(x - 2) - 4(x - 2) = (x - 4)(x - 2)
f) x2 - 5x - 14 = x2 - 7x + 2x - 14 = x(x - 7) + 2(x - 7) = (x + 2)(x - 7)
g) x2 + 6x + 5 = x2 + 5x + x + 5 = x(x + 5) + (x + 5) = (x + 1)(x + 5)
h) x2 - 7x + 12 = x2 - 3x - 4x + 12 = x(x - 3) - 4(x - 3) = (x - 4)(x - 3)
i) x2 - 7x + 10 = x2 - 2x - 5x + 10 = x(x - 2) - 5(x - 2) = (x - 5)(x - 2)
Oh Sehun:Ít một thôi bạn ơi!Làm xong đống này chắc đến tuổi già mất:(
a
\(x^2-5x+6\)
\(=\left(x^2-3x\right)-\left(2x-6\right)\)
\(=\left(x-3\right)\left(x-2\right)\)
b
\(3x^2+9x-30\)
\(=x^2+3x-10\)
\(=\left(x^2-2x\right)+\left(5x-10\right)\)
\(=\left(x-2\right)\left(x+5\right)\)
c
\(x^2-3x+2\)
\(=\left(x^2-x\right)-\left(2x-2\right)\)
\(=\left(x-1\right)\left(x-2\right)\)
d
\(x^2-9x+18\)
\(=\left(x^2-3x\right)-\left(6x-18\right)\)
\(=\left(x-3\right)\left(x-6\right)\)
e
\(x^2-6x+8\)
\(=\left(x^2-2x\right)-\left(4x-8\right)\)
\(=\left(x-2\right)\left(x-4\right)\)
f
\(x^2-5x-14\)
\(=\left(x^2+2x\right)-\left(7x+14\right)\)
\(=\left(x+2\right)\left(x-7\right)\)
g
\(x^2+6x+5\)
\(=\left(x^2+x\right)+\left(5x+5\right)\)
\(=\left(x+1\right)\left(x+5\right)\)
h
\(x^2-7x+12\)
\(=\left(x^2-3x\right)-\left(4x-12\right)\)
\(=\left(x-3\right)\left(x-4\right)\)
i
\(x^2-7x+10\)
\(=\left(x^2-2x\right)-\left(5x-10\right)\)
\(=\left(x-2\right)\left(x-5\right)\)
P/S:Cho e xin phép tách câu ạ.