Đặt a/2 = b/5 = c/7 => a=2k,b=5k,c=7k
Ta có: \(A=\frac{a-b+c}{a+2b-c}=\frac{2k-5k+7k}{2k+2.5k-7k}=\frac{4k}{5k}=\frac{4}{5}\)
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cho\(\frac{a}{2}=\frac{b}{5}=\frac{c}{7}\)tim gia tri cua bieu thuc \(A=\frac{a-b+c}{a+2b-c}\)
ban nao giup minh voi cho a/3=b/6=c/7.Tinh gia tri bieu thuc C=a-2b+c/a+b-2c
cho A = ( x-5 )B = ( b+6 ) tim gia tri nho nhat cua bieu thuc C=A+B
tim gia tri lon nhat cua bieu thuc :
a) C= 5+ 15/ 4 I 3x+7 I +3
b) D= 2 I 7x+5I +11/ I 7x+5I +4
tim GTNN cua bieu thuc :
a) A= I x+1I + 1,7
b) B= I x-2/3I +3/7
c) C= 5+ -8/ 4x I5x+7I 24
tim gia tri lon nhat cua bieu thuc :
a) C= 5+ 15/ 4 I 3x+7 I +3
b) D= 2 I 7x+5I +11/ I 7x+5I +4
tim gia tri lon nhat cua bieu thuc :
a) C= 5+ 15/ 4 I 3x+7 I +3
b) D= 2 I 7x+5I +11/ I 7x+5I +4
tinh gia tri bieu thuc
/a+b-c/
biet A= -5 ; B=2;C=1
BIET / LA GIA TRI tuyet doi
TIM GIA TRI LON NHAT CUA BIEU THUC :
C=2+12/3x/X+5/+4
TIM GIA TRI NHO NHAT CUA BIEU THUC
C= -15/ 4x / 3X+7/+3
Tim cac gia tri nguyen cua x de cac gia tri bieu thuc sau la so nguyen
a, 9-2x/x-3
b,3x-5/x-2
c,-3/4-x