Question

WYRAŻENIA ALGEBRAICZNE...!
Wykonaj działania:

a) (m+n)(m-2)+(m-n)(m+n)

b) (3x-2)(3x-2y+1)-4x(2x-3y+1)

c) 3(m+1)(n-2)+2(n+1)(m-2)

d) x(x+1)(x+2)-x(x-1)(x-2)

Answer 1

a)

(m+n)(m-2)+(m-n)(m+n)=

m²-2m+mn-2n+m²+mn-mn-n²=

2m²+mn-n²-2m-2n

 

b)

(3x-2)(3x-2y+1)-4x(2x-3y+1)=

9x²-6xy+3x-6x+4y-2-8x²+12xy-4x=

x²+6xy-7x+4y-2

 

c)

3(m+1)(n-2)+2(n+1)(m-2)=

3(mn-2m+n-2)+2(mn-2n+m-2)=

3mn-6m+3n-6+2mn-4n+2m-4=

5mn-4m-n-10

 

d)

x(x+1)(x+2)-x(x-1)(x-2)=

x(x²+2x+x+2)-x(x²-2x-x+2)=

x³+2x²+x²+2x-x³+2x²+x²-2x=

6x²