Question

Cześć prosze rozwiozanie zad plis to na jutro.

Zad 17 str 86 z starych z mamtmy z nowych 91

a) (m+n)(m-2)+(m-n)(m+1)
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)

Z Góry dzięki daje NAJ

Answer 1

a)(m+n)(m-2)+(m-n)(m+1)=m^2-2m+mn-2n+m^2+m-mn-n =2m^2-m-3n

 

b)(3x-2)(3x-2y+1)-4x(2x-3y+1)=9x^2-6xy+3x-6x+4y-2 -8x^2+12xy-4x =x^^2+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)=x(x^2+3x+2)-x(x^2-3x+2)=x^3+3x^2+2x-x^3+3x^2-2x=6x^2

Answer 2

a)  (m+n)(m-2) + (m-n)(m+1) = m²-2m+mn-2n +m²+m-mn-n =2m²-m-3n

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) = x(x²+3x+2) -x(x²-3x+2) =

                                       = x³+3x²+2x-x³+3x²-2x = 6x²