cho a/b+c+d=b/c+d+a=c/d+a+b=d/b+c+a
tính M = (a+b/c+d)+(b+c/a+d)+(c+d/a+b)+(d+a/b+c)
Những câu hỏi liên quan
1, Cho a/b = c/d . C/m (a+b/c+d)^2=a^2+b^2/c^2+d^2 ?
2, Cho (a+b+c+d)(a-b-c+d)=(a-b+c-d)(a+b-c-d)
C/m a/b=c/d ?
cho : a/b+c+d = b/ c+d+a = c/d+a+b = d/a+b+c
tính : M = a+b/c+d = b+c/d+a= c+d/a+b = d+a/b+c
Cho a, b, c, d thỏa mãn : b+c+d/a=a+c+d/b=a+b+d/c=a+b+c/d
Tính M= a/b+c+d + b/a+c+d + c/a+b+d + d/a+b+c
Answer:
Có vài chỗ mình sửa lại đề nhé!
Áp dụng tính chất của dãy tỉ số bằng nhau
\(\frac{a}{b+c+d}=\frac{b}{a+c+d}=\frac{c}{a+b+d}=\frac{d}{a+b+c}=\frac{a+b+c+d}{b+c+d+a+c+d+a+b+d+a+b+c}\)
\(\Rightarrow\frac{a}{b+c+d}=\frac{b}{a+c+d}=\frac{c}{a+b+d}=\frac{d}{a+b+c}=\frac{a+b+c+d}{3a+3b+3c+3d}=\frac{1}{3}\)
\(\Rightarrow3a=b+c+d\)
\(\Rightarrow3b=a+c+d\)
\(\Rightarrow3c=a+b+d\)
\(\Rightarrow3d=a+b+c\)
Ta có:
\(3a+3b=b+c+d+a+c+d\)
\(\Rightarrow3.\left(a+b\right)=a+b+2c+2d\)
\(\Rightarrow2.\left(a+b\right)=2.\left(c+d\right)\)
\(\Rightarrow a+b=c+d\)
Tương tự:
\(\Rightarrow b+c=a+d\)
\(\Rightarrow c+d=a+b\)
\(\Rightarrow d+a=b+c\)
Ta có:
\(M=\frac{a+b}{c+d}+\frac{b+c}{a+d}+\frac{c+d}{a+b}+\frac{d+a}{b+c}\)
\(=\frac{a+b}{a+b}+\frac{b+c}{b+c}+\frac{c+d}{c+d}+\frac{d+a}{d+a}\)
\(=1\)
cho 2016a+b+c+d/a=a+2016b+c+d/b=a+b+2016c+d/c=a+b+c+2016d/d tính M=a+b/c+d + c+d/d+a + c+d/a+b + d+a/b+c
\(\frac{2016a+b+c+d}{a}=\frac{a+2016b+c+d}{b}=\frac{a+b+2016c+d}{c}=\frac{a+b+c+2016d}{d}\)
\(\Rightarrow\frac{2016a}{a}+\frac{b+c+d}{a}=\frac{2016b}{b}+\frac{a+c+d}{b}=\frac{2016c}{c}+\frac{a+b+d}{c}=\frac{2016d}{d}+\frac{a+b+c}{d}\)
\(\Rightarrow2016+\frac{b+c+d}{a}+1=2016+\frac{a+c+d}{b}+1=2016+\frac{a+b+d}{c}+1=2016+\frac{a+b+c}{d}+1\)
\(\Rightarrow\frac{a+b+c+d}{a}=\frac{a+b+c+d}{b}=\frac{a+b+c+d}{c}=\frac{a+b+c+d}{d}\)
\(\Rightarrow a=b=c=d\)
\(Khiđó:M=1+1+1+1=4\)
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Cho : 2*a+b+c+d/a =a+2*b+c+d/b =a+b+2*c+d/c =a+b+c+2*d/d . Tính M=a+b/c+d -b-c/d+a +c+d/a+d*d+a/b+c .Giúp mình với!
cho: 2a+b+c+d/a=a+2b+c+d/b=a+b+2c+d/c=a+b+c+2d/d.Tính M=a+b/c+d + b+c/d+a + c+d/a+b + d+a/b+c
Ta có\(\frac{2a+b+c+d}{a}=\frac{a+2b+c+d}{b}=\frac{a+b+2c+d}{c}=\frac{a+b+c+2d}{d}\)
=> \(\frac{2a+b+c+d}{a}-1=\frac{a+2b+c+d}{b}-1=\frac{a+b+2c+d}{c}-1=\frac{a+b+c+2d}{d}-1\)
=> \(\frac{a+b+c+d}{a}=\frac{a+b+c+d}{b}=\frac{a+b+c+d}{c}=\frac{a+b+c+d}{d}\)
Khi a + b + c + d = 0
=> a + b = -(c + d)
b + c = -(a + d)
Khi đó \(M=\frac{a+b}{c+d}+\frac{b+c}{d+a}+\frac{c+d}{a+b}+\frac{a+d}{b+c}\)
\(=\frac{-\left(c+d\right)}{c+d}+\frac{-\left(a+d\right)}{a+d}+\frac{c+d}{-\left(c+d\right)}+\frac{a+d}{-\left(a+d\right)}=-1+\left(-1\right)+\left(-1\right)+\left(-1\right)\)= -4
Nếu a + b + d + d \(\ne\)0
=> \(\frac{1}{a}=\frac{1}{b}=\frac{1}{c}=\frac{1}{d}\Rightarrow a=b=c=d\)
Khi đó M = \(\frac{a+b}{c+d}+\frac{b+c}{d+a}+\frac{c+d}{a+b}+\frac{d+a}{b+c}=\frac{2a}{2a}+\frac{2b}{2b}+\frac{2c}{2c}+\frac{2d}{2d}=1+1+1+1=4\)
Vậy khi a + b + c + d = 0 => M = -4
khi a + b + c + d \(\ne\)0 => M = 4
cho 2a+b+c+d / a = a+2b+c+d / b = a+b+2c+d = a+b+c+2d / d
tính M = a+b / c+d + b+c / d+a + c+d / a+b + d+a / b+c
Cho biểu thức sau:$\frac{2a+b+c+d}{a}$2 a + b + c + d a bam vao do nho bam lik e :\
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cho các số a, b,c,d sao cho a+b+c/a = a+b+d/c= a+c+d/b= c+b+d/a
Tính giá trị biểu thức dưới đây M= d/a+b+c=c/a+b+d= b/a+c+d=a/c+b+d
Cho a;b;c;d khác 0. Thỏa mãn a/b+c+d = b/a+d+c = c/a+b+d = d/a+b+c.CMR M=a+b/c+d + b+c/a+d + c+d/a+b + d+a/b+c không phải là số chính phương