Giúp mk bài này với ạ a, x2(5×3-x-1_2) B,(3xy-x2+y) 2_3 x2y C, (4×3 -5xy+2x) (-1_2xy) 05/08/2021 Bởi Elliana Giúp mk bài này với ạ a, x2(5×3-x-1_2) B,(3xy-x2+y) 2_3 x2y C, (4×3 -5xy+2x) (-1_2xy)
Giải thích các bước giải: a/ `x^2(5x^3-x-\frac{1}{2})` $=x^2.5x^3-x^2.x-x^2.\dfrac{1}{2}$ $=5x^5-x^3-\dfrac{1}{2}x^2$ b/ $(3xy-x^2+y).\dfrac{2}{3}x^2y$ $=3xy.\dfrac{2}{3}x^2y-x^2.\dfrac{2}{3}x^2y+y.\dfrac{2}{3}x^2y$ $=2x^3y^2-\dfrac{2}{3}x^4y+\dfrac{2}{3}x^2y^2$ c/ `(4x^3-5xy+2x)(-\frac{1}{2}xy)` $=-\dfrac{1}{2}xy.4x^3+\dfrac{1}{2}xy.5xy-\dfrac{1}{2}xy.2x$ $=-2x^4y+\dfrac{5}{2}x^2y^2-x^2y$ Chúc bạn học tốt !!! Bình luận
a) `x²(5x³-x-1/2)` `= x².5x³-x².x-x².1/2` `= 5x^5-x³-1/2x²` b) `(3xy-x²+y). 2/3x²y` `= 2x³y²-2/3x^4y+2/3x²y²` c) `(4x³-5xy+2x)(-1/2xy)` `= -2x^4y+5/2x²y²-x²y` Bình luận
Giải thích các bước giải:
a/ `x^2(5x^3-x-\frac{1}{2})`
$=x^2.5x^3-x^2.x-x^2.\dfrac{1}{2}$
$=5x^5-x^3-\dfrac{1}{2}x^2$
b/ $(3xy-x^2+y).\dfrac{2}{3}x^2y$
$=3xy.\dfrac{2}{3}x^2y-x^2.\dfrac{2}{3}x^2y+y.\dfrac{2}{3}x^2y$
$=2x^3y^2-\dfrac{2}{3}x^4y+\dfrac{2}{3}x^2y^2$
c/ `(4x^3-5xy+2x)(-\frac{1}{2}xy)`
$=-\dfrac{1}{2}xy.4x^3+\dfrac{1}{2}xy.5xy-\dfrac{1}{2}xy.2x$
$=-2x^4y+\dfrac{5}{2}x^2y^2-x^2y$
Chúc bạn học tốt !!!
a) `x²(5x³-x-1/2)`
`= x².5x³-x².x-x².1/2`
`= 5x^5-x³-1/2x²`
b) `(3xy-x²+y). 2/3x²y`
`= 2x³y²-2/3x^4y+2/3x²y²`
c) `(4x³-5xy+2x)(-1/2xy)`
`= -2x^4y+5/2x²y²-x²y`