\(H=\left(m:1-mx1\right):\left(mx1991+m+1\right)\)

\(=\left(m-m\right):\left(mx1991+m+1\right)\)

\(=0:\left(mx1991+m+1\right)\)

\(=0\)

H = ( m : 1 - m x 1 ) : ( m x 1991 + m+ 1 )

H = ( m - m ) : ( m x 1991 + m + 1 )

H = 0 : ( m x 1991 + m +1 )

H = 0

bài làm  :     h = ( m - m ) : ( m x 1991 + m + 1 )

                  h = 0 : (m x 1991 +m + 1 )

                  h = 0

tích nha, tích lại cho

H=0

hehehe

h = ( m - m ) : ( m x 1991 + m + 1 )

h = 0 : ( m x 1991 + m + 1 )

h = 0 

Câu hỏi:   tính giá trị biểu thức

H = [ m : 1 - m * 1 ] : [ m * 1991 + m + 1 ]

Trả lời: H = [ m : 1 - m * 1 ] : [ m * 1991 + m + 1 ]

= H = [ m - m ] : [ m * 1991 + m + 1 ] = H = 0 : [ m * 1991 + m + 1 ] = 0.

\(H=\left(m-m\right):\left(m.1991+m+1\right)\)

\(H=0:\left(m.1991+m+1\right)\)

\(H=0\)

H = ( m : 1 - m x 1 ) : ( m x 1991 + m + 1 )

= ( m - m ) : ( m x 1991 + m + 1 )

= 0 : ( m x 1991 + m + 1 )

= 0.

đề bài là j z??!!!!!

đề bài là gì vậy hả PewDiePie

Đề bài là tìm m khi biết:

(m x 1 x m : 1)  :  (m : 1991 x m :1)

Câu 1 :

Số các số chia hết cho \(2\) là :

    \(\left(2000-2\right)\div2+1=1000\)

       Đáp số : \(1000\) số chia hết cho \(2\) .

Câu 2 :

\(H=\left(m\div1-m\times1\right)\div\left(m\times1991+m+1\right)\)

\(H=\left(m-m\right)\div\left(m\times1991+m+1\right)\)

\(H=0\div\left(m\times1991+m+1\right)\)

\(H=0\)

  H = ( m : 1 - m *1 ) : ( m *1991 + m + 1 ) 

H=(m-m):(m*1991+m+1)

H=0:(m*1991+m+1)

H=0

H= (m:1-m X 1) : (m X 1991 + m + 1)

= ( m - m ) : (m X1991 + m +1 )

= 0 : ( m X 1991 + m + 1 )

= 0

H = ( m : 1 - m x 1 ) : ( m x 1991 +  m + 1 )

H = ( m - m ) : ( m x 1991 + m + 1 )

H = 0 : ( m x 1991 + m + 1 )

H = 0 ( vì 0 chia cho số nào cũng bằng 0 )

\(M=\frac{5}{1.6}+\frac{5}{6.11}+\frac{5}{11.16}+....+\frac{5}{46.51}\)

\(M=\frac{6-1}{1.6}+\frac{11-6}{6.11}+\frac{16-11}{11.16}+...+\frac{51-46}{46.51}\)

\(M=1-\frac{1}{6}+\frac{1}{6}-\frac{1}{11}+\frac{1}{11}-\frac{1}{16}+....+\frac{1}{46}-\frac{1}{51}\)

\(M=1-\frac{1}{51}=\frac{50}{51}\)

\(N=\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+....+\frac{1}{199\cdot201}\)

\(N=\frac{1}{2}.\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+....+\frac{1}{199}-\frac{1}{201}\right)\)

\(N=\frac{1}{2}\cdot\left(1-\frac{1}{201}\right)\)

\(N=\frac{1}{2}\cdot\frac{200}{201}=\frac{100}{201}\)

a: \(P=\left(\dfrac{1}{m\left(m-1\right)}+\dfrac{1}{m-1}\right)\cdot\dfrac{\left(m-1\right)^2}{m+1}\)

\(=\dfrac{m+1}{m\left(m-1\right)}\cdot\dfrac{\left(m-1\right)^2}{m+1}=\dfrac{m-1}{m}\)

b: Khi m=1/2 thì \(P=\left(\dfrac{1}{2}-1\right):\dfrac{1}{2}=\dfrac{-1}{2}\cdot2=-1\)