Câu hỏi của Như Trần

Question

A = 4x – x2 + x2y – 1 +  y

B = x2 + 5y – 6x +  + 3xy2

Tinh A + B, A-B, B-A

giup em voi a, cau nao cung dc ! Cam on truoc a

Aki Tsuki · Accepted Answer

mk lm 1 phép +, 1 phép - phép - còn lại bn tự lm nhé!

$A+B=\left(4x-x^2+x^2y-1+y\right)+\left(x^2+5y-6x+3xy^2\right)$$=4x-x^2+x^2y-1+y+x^2+5y-6x+3xy^2$

$=\left(4x-6x\right)+\left(x^2-x^2\right)+\left(y+5y\right)+x^2y+3xy^2-1$

$=-2x+6y+x^2y+3xy^2-1$

$A-B=\left(4x-x^2+x^2y-1+y\right)-\left(x^2+5y-6x+3xy^2\right)$ $=4x-x^2+x^2y-1+y-x^2-5y+6x-3xy^2$

$=\left(4x+6x\right)+\left(-x^2-x^2\right)+\left(y-5y\right)-x^2y-3xy^2-1$

$=10x-2x^2-4y-x^2y-3xy^2-1$Câu trả lời: mk lm 1 phép +, 1 phép - phép - còn lại bn tự lm nhé!

$A+B=\left(4x-x^2+x^2y-1+y\right)+\left(x^2+5y-6x+3xy^2\right)$$=4x-x^2+x^2y-1+y+x^2+5y-6x+3xy^2$

$=\left(4x-6x\right)+\left(x^2-x^2\right)+\left(y+5y\right)+x^2y+3xy^2-1$

$=-2x+6y+x^2y+3xy^2-1$

$A-B=\left(4x-x^2+x^2y-1+y\right)-\left(x^2+5y-6x+3xy^2\right)$ $=4x-x^2+x^2y-1+y-x^2-5y+6x-3xy^2$

$=\left(4x+6x\right)+\left(-x^2-x^2\right)+\left(y-5y\right)-x^2y-3xy^2-1$

$=10x-2x^2-4y-x^2y-3xy^2-1$

tran khoi my · Answer

B-A=(x$^2$+5y-6x+3xy$^2$)-(4x-x$^2$+x$^2$y-1+y)

= x$^2$+5y-6x+3xy$^2$-4x+x$^2$-x$^2$y+1-y

=(x$^2$+x$^2$)+(5y-y)+(-6x-4x)+3xy$^2$-x$^2$y+1

=2x$^2$+4y-10x+3xy$^2$-x$^2$y+1Câu trả lời: B-A=(x$^2$+5y-6x+3xy$^2$)-(4x-x$^2$+x$^2$y-1+y)

= x$^2$+5y-6x+3xy$^2$-4x+x$^2$-x$^2$y+1-y

=(x$^2$+x$^2$)+(5y-y)+(-6x-4x)+3xy$^2$-x$^2$y+1

=2x$^2$+4y-10x+3xy$^2$-x$^2$y+1

Đại số lớp 7