Phân tích đa thức thành nhân tử-Tách,Thêm Bớt a,8x^2+10x-3 b,8x^2-2x-1 c,x^3-9x^2+14x d,6x^2+7xy+2y^2 18/07/2021 Bởi Harper Phân tích đa thức thành nhân tử-Tách,Thêm Bớt a,8x^2+10x-3 b,8x^2-2x-1 c,x^3-9x^2+14x d,6x^2+7xy+2y^2
a, 8x²+10x-3 = 8x²+6x+4x-3 = 2x(4x+3)+1(4x+3) = (2x+1)(4x+3) b, 8x²-2x-1 = 8x²-4x+2x-1 = 4x(2x-1)+1(2x-1) = (4x+1)(2x-1) c, x³-9x²+14x = x³-2x²-7x²+14x = x²(x-2)-7x(x-2) = (x²-7x)(x-2) d, 6x²+7xy+2y² = 6x²+3xy+4xy+2y² = 3x(2x+y)+2y(2x+y) = (3x+2y)(2x+y) CHÚC BẠN HỌC TỐT Bình luận
Đáp án: $a, 8x²+ 10x – 3$ $= 8x² – 2x + 12x – 3$ $= 2x(4x – 1) + 3(4x – 1)$ $= (4x – 1)(2x + 3)$ $b, 8x² – 2x – 1$ $= 8x² – 4x + 2x – 1$ $= 4x(2x – 1) + (2x-1)$ $= (4x + 1)(2x – 1)$ $c, x³- 9x² + 14x$ $= x³ – 2x² – 7x² + 14x$ $= x²(x – 2) – 7x(x – 2)$ $= (x² – 7x)(x – 2)$ $= x(x – 7)(x – 2)$ $d, 6x²+ 7xy + 2y²$ $= 6x² + 3xy + 4xy + 2y²$ $= 3x(2x + y) + 2y (2x + y)$ $= (3x + 2y)(2x + y)$ Bình luận
a, 8x²+10x-3
= 8x²+6x+4x-3
= 2x(4x+3)+1(4x+3)
= (2x+1)(4x+3)
b, 8x²-2x-1
= 8x²-4x+2x-1
= 4x(2x-1)+1(2x-1)
= (4x+1)(2x-1)
c, x³-9x²+14x
= x³-2x²-7x²+14x
= x²(x-2)-7x(x-2)
= (x²-7x)(x-2)
d, 6x²+7xy+2y²
= 6x²+3xy+4xy+2y²
= 3x(2x+y)+2y(2x+y)
= (3x+2y)(2x+y)
CHÚC BẠN HỌC TỐT
Đáp án:
$a, 8x²+ 10x – 3$
$= 8x² – 2x + 12x – 3$
$= 2x(4x – 1) + 3(4x – 1)$
$= (4x – 1)(2x + 3)$
$b, 8x² – 2x – 1$
$= 8x² – 4x + 2x – 1$
$= 4x(2x – 1) + (2x-1)$
$= (4x + 1)(2x – 1)$
$c, x³- 9x² + 14x$
$= x³ – 2x² – 7x² + 14x$
$= x²(x – 2) – 7x(x – 2)$
$= (x² – 7x)(x – 2)$
$= x(x – 7)(x – 2)$
$d, 6x²+ 7xy + 2y²$
$= 6x² + 3xy + 4xy + 2y²$
$= 3x(2x + y) + 2y (2x + y)$
$= (3x + 2y)(2x + y)$