Question

Zapisz w jak najprostrzej postaci

a) (x-2) -(2-x)

b) (a+b)+ (2a-b) -(a-2b)

c) (3x-y+1)- x+y)+(y-x)

d) -(2a²-3ab)- (2b-3a²)+(-ab-b)

Answer 1

a)
(x - 2) - (2 - x) =
= x - 2 - 2 + x =
= 2x - 4

b)
(a + b) + (2a - b) - (a - 2b) =
= a + b + 2a - b - a + 2b =
= 2a + 2b

c)
(3x - y + 1) - (x + y) + (y - x) =
= 3x - y + 1 - x - y + y - x =
= x - y + 1

d)
-(2a² - 3ab) - (2b - 3a²) + (-ab - b) =
= -2a² + 3ab - 2b + 3a² - ab - b =
= a² + 2ab - 3b

Answer 2

a)

(x-2) -(2-x)=x-2-2+x=2x-4

b)

(a+b)+ (2a-b) -(a-2b)=a+b+2a-b-a+2b=2a+2b

c)

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

d)

-(2a²-3ab)- (2b-3a²)+(-ab-b)=-2a²+3ab-2b+3a²-ab-b=a²+2ab-3b