Rút gọn biểu thức sau :
a) -(a-c)-(a-b+c)
b) -(a-b+c)-(a+b+c)
c) (a+b)-(a-b)+(a-c)-(a+c)
d) (a+b-c)+(a-b+c)-(b+c-a)-(a-b-c)
rút gọn biểu thức sau
D = (a + b - c) - (a - b + c) + (b + c - a) - ( a - b - c)
các bạn giải giùm mình nhé
\(D=\left(a+b-c\right)-\left(a-b+c\right)+\left(b+c-a\right)-\left(a-b-c\right)\)
\(D=a+b-c-a+b-c+b+c-a-a+b+c\)
\(D=\left(a-a-a-a\right)+\left(b+b+b+b\right)+\left(c+c-c-c\right)\)
\(D=4b-3a\)
Bỏ ngoặc rồi rút gọn biểu thức:
a) - ( - a + c – d ) – ( c – a + d ) ; b) – ( a + b - c + d ) + ( a – b – c –d )
c) a( b – c – d ) – a ( b + c – d ) ; d)(a+ b) ( c + d) – ( a + d ) ( b + c )
e)( a + b ) ( c – d ) – ( a – b ) ( c + d ) ; f) ( a + b ) 2 – ( a – b ) 2
a) - ( - a + c – d ) – ( c – a + d )
= a - c - d - c + a + d
= (a + a) + (-c - c) + (-d + d)
= 2a - 2c
b) – ( a + b - c + d ) + ( a – b – c –d )
= - a - b + c - d + a - b - c - d
= (-a + a) + (-b - b) + (c - c) + (-d - d)
= -2b - 2d
a) - ( - a + c - d) - ( c - a + d )
= a - c + d - c + a - d
= 2a
b) - ( a+ b - c + d ) + ( a -b -c -d )
= - a-b+c-d+a-b-c-d
=-2d -2b
c) a(b-c-d) - a(b+c-d)
= a(b-c-d-b-c+d)
= ab-ac-ad-ab-ac+ad
= -2ab-2ac
d) (a+b)(c+d)-(a+d)(b+c)
= ac+ad+bc+bd - (ab+ac+bd+cd)
= ac+ad+bc+bd-ab-ac-bd-cd
=ad+bc-ab-cd
a) - ( - a + c - d) - ( c - a + d )
= a - c + d - c + a - d
= 2a
b) - ( a+ b - c + d ) + ( a -b -c -d )
= - a-b+c-d+a-b-c-d
=-2d -2b
c) a(b-c-d) - a(b+c-d)
= a(b-c-d-b-c+d)
= ab-ac-ad-ab-ac+ad
= -2ab-2ac
d) (a+b)(c+d)-(a+d)(b+c)
= ac+ad+bc+bd - (ab+ac+bd+cd)
= ac+ad+bc+bd-ab-ac-bd-cd
=ad+bc-ab-cd
e)(a+b)(c-d)-(a-b)(c+d)
= ac-ad+bc-bd-ac-ad+bc+bd
= 2bc-2ad
f) ( a + b )2 – ( a – b )2
= a2+2ab+b2 - (a2+2ab-b2)
=a2+2ab+b2 - a2-2ab+b2
=2b2
rút gọn các biểu thức sau:
A=(a - b)+( a+b+c)-(a-b-c)
B=(a-b)-(b-c)+(c-a)-(a-b-c)
C=(-a +b +c)-(a-b+c)-(a+b-c)
A=(a-b)+(a+b+c)-(a-b-c)
=a-b+a+b+c-a+b+c
=(a+a-a)+(-b+b+b)+(c+c)
= a+b+c.2
= a+b+2c
B=(a-b)-(b-c)+(c-a)-(a-b-c)
=a-b-b+c+c-a-a+b+c
=(a-a-a)+(-b-b+b)+(c+c+c)
= (-a)+ (-b) +c.3
= (-a)+(-b)+3c
C=(-a+b+c)-(a-b+c)-(a+b-c)
= (-a)+b+c-a+b-c-a-b+c
=(-a-a-a)+(b+b-b)+(c-c+c)
= (-a.3) +b+c
rút gọn các biểu thức sau
a,A=(a-b)+(a+b-c)-(a-b-c)
b,B=(a-b)-(b-c)+(c-a)-(a-b-c)
c,C=(-a+b+c)-(a-b+c)-(a-b+c)-(-a+b-c)
B1:bỏ ngoặc rồi rút gọn các biểu thức sau:
a,(a+b)-(a-b)+(a-c)-(a+c)
b, (a+b-c)+(a-b+c)-(b+c-a)-(a-b-c)
B2:xét biểu thức N= -{-(a+b)-[(a-b)-(a+b)]}
bỏ ngoặc và thu gọn
B1:
a, a+b+(-a)+b+a+(-c)+(-a)+(-c)=[a+(-a)+a+(-a)]+(b+b)+[(-c)+(-c)]=0+2.b+(-2).c
b, a+b+(-c)+a+(-b)+c+(-b)+(-c)+a+(-a)+b+c=[a+a+a+(-a)]+[b+(-b)+(-b)+b]+[(-c)+c+(-c)+c]=2.a+0+0=2a
B2:
N=(a+b)-(a-b)+(a+b)=a+b+(-a)+b+a+b=[a+(-a)+a)+(b+b+b)=a+3.b
NẾU CẬU KHÔNG HIỂU THÌ CỨ HỎI NHÉ!
rút gọn biểu thức
a,A=(a-b)-(a-b+c)
b,B=-(a+b+c)-(a+b-5)
Rút gọn các biểu thức sau
a) A=(a-b) + (a+b-c) - (a-b-c)
b) B=(a-b) - (b-c) + (c-a) - (a-b-c)
c) C=(-a+b+c) - (a-b+c) - ( -a+b-c)
a, A = (a - b) + (a + b - c) - (a - b - c)
= a - b + a + b - c - a + b + c
= a + b
b, B = (a - b) - (b - c) + (c - a) - (a - b - c)
= a - b - b + c + c - a - a + b + c
= - a - b + 3c
c, C = ( - a + b + c) - (a - b + c) - ( -a + b - c)
= -a + b + c - a + b - c + a - b + c
= -a + b + c
\(a,A=\left(a-b\right)+\left(a+b-c\right)-\left(a-b-c\right)\)
\(=a-b+a+b-c-a+b+c\)
\(=a+b\)
\(b,B=\left(a-b\right)-\left(b-c\right)+\left(c-a\right)-\left(a-b-c\right)\)
\(=a-b-b+c+c-a-a+b+c\)
\(=-a-b+3c\)
\(c,C=\left(-a+b+c\right)-\left(a-b+c\right)-\left(-a+b-c\right)\)
\(=-a+b+c-a+b-c+a-b+c\)
\(=-a+b+c\)
A=(a-b)+(a+b-c)-(a-b-c)
=a-b+a+b-c-a+b+c
=a+(-b)+a+b+(-c)+(-a)+b+c
=a+b
B=(a-b)-(b-c)+(c-a)-(-a+b-c)
=a+b-b+c+c-a+a-b+c
=a+b+(-b)+c+c+(-a)+a+(-b)+c
=a+(-b)+3c
C=(-a+b+c)-(a-b+c)-(-a+b-c)
=-a+b+c-a+b-c+a-b+c
=-a+b+c+(-a)+b+(-c)+a+(-b)+c
=-a+b+c
Rút gọn các biểu thức sau:
a) A= (a-b)+(a+b-c)-(a-b-c)
b) B= (a-b)-(b-c)+(c-a)-(a-b-c)
c) C= (-a+b+c)-(a-b+c)-(-a+b-c)
a. A = (a-b)+(a+b-c)-(a-b-c)=a-b+a+b-c-a+b+c=(a-a+a) + (b-b+b)+(c-c)=4+3+0=4+b
b.B=(a-b)-(b-c)+(c-a)-(a-b-c)=a-b-b+c+c-a-a+b+c=(a-a-a)+(b-b-b)+(c+c+c)=-a+(-b)+3c
c.C=(-a+b+c)-(a-b+c)-(-a+b-c)=-a+b+c+b-a+b-c-a-b+c= -(a+a+a)+(b+b+b)+(c+c-c)=-3a+3b+c
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Bài 1: bỏ dấu ngoặc rồi rút gọn biểu thức a, - ( - a + c - d ) - ( c - d + d) b, - ( a + b - c + d ) + (a - b - c - d) c, a( b - c - d ) - a( b + c -d ) d*, (a + b).(c+d) - ( a+d).(b+c) e*, (a+b).(c-d) - (a-b).(c+d) f*, (a+b)2 - (a-b)2
a, -( -a + c - d) - ( c - d + d) = a - c + d - c + d - d = a + d
b, - ( a+b-c+d) + (a-b-c-d) = -a -b+c-d + a-b-c-d = -2b + (-2c)= -2(b+c)
Rút gọn các biểu thức sau:
a) A=(a-b)+(a+b-c)-(a-b-c)
b) B=(a-b)-(b-c)+(c-a)-(a-b-c)
c) C=(-a+b+c)-(a-b+c)-(-a+b-c)
Giúp mk với^^
a) A=(a-b)+(a+b-c)-(a-b-c)=a+b
b) B=(a-b)-(b-c)+(c-a)-(a-b-c)=-a-b+3c
c) C=(-a+b+c)-(a-b+c)-(-a+b-c)=-a+b+c
A = ( a - b ) + ( a + b - c ) - ( a - b - c )
A = a - b + a + b - c - a + b + c
A = a + b
B = ( a - b ) - ( b - c ) + ( c - a ) - ( a - b - c )
B = a - b - b + c + c - a - a + b + c
B = -a - b + 3c
C = ( -a + b + c ) - ( a - b + c ) - ( -a + b - c )
C = -a + b + c - a + b - c + a - b + c
C = -a + b + c
a, \(A=\left(a-b\right)+\left(a+b-c\right)-\left(a-b-c\right)\)
\(=a-b+a+b-c-a+b+c=a+b\)
b, \(B=\left(a-b\right)-\left(b-c\right)+\left(c-a\right)-\left(a-b-c\right)\)
\(=a-b-b+c+c-a-a+b+c=-a-b+3c\)
c, \(C=\left(-a+b+c\right)-\left(a-b+c\right)-\left(-a+b-c\right)\)
\(=-a+b+c-a+b-c+a-b+c=-a+b+c\)