\(\frac{3}{4}+\frac{3}{28}+\frac{3}{70}+...+\frac{3}{10300}\)

\(=\frac{3}{1\times4}+\frac{3}{4\times7}+\frac{3}{7\times10}+...+\frac{3}{100\times103}\)

\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+...+\frac{1}{100}-\frac{1}{103}\)

\(=1-\frac{1}{103}=\frac{102}{103}\)

\(4\left(x-1\right)-3\left(x-2\right)=-5\)

\(\Leftrightarrow4x-4-3x+6=-5\)

\(\Leftrightarrow x=-5+4-6\)

\(\Leftrightarrow x=-7\)

Vậy x=-7

Ta có: 4(x-1) - 3(x-2) = -5

          (4x-4) - (3x-6) = -5

          4x - 4 - 3x + 6 = -5 

     (4x - 3x) + (-4+6) = -5

                       x + 2  = -5

                             x  = -5 - 2

                              x = -7

                         Vậy x = -7

\(x-3=2x+4\)

\(x-2x=3+4\)

\(-1x=7\)

\(x=\frac{7}{-1}\)

\(x=-7\)

\(x-3=2x+4\)

\(\Rightarrow x-2x=4+3\)

\(x.\left(1-2\right)=7\)

\(x.\left(-1\right)=7\)

\(x=-7\)

CHÚC BẠN HỌC TỐT!!!

16 . 4^x = 4⁸

4² . 4^x = 4⁸

       4^x = 4⁸ : 4²

       4^x = 4⁶

=> x=6

Học tốt

Sgk

16 . 4^x = 4⁸ 

16 . 4^x = 65536

       4^x = 65536 : 16

       4^x =     4096

       4^x =   4⁶

=>   x = 6

a, | x - 3/4 | = 1/2

=>\(\orbr{\begin{cases}x-\frac{3}{4}=\frac{1}{2}\\x-\frac{3}{4}=-\frac{1}{2}\end{cases}}\)

=>\(\orbr{\begin{cases}x=\frac{1}{2}+\frac{3}{4}\\x=-\frac{1}{2}+\frac{3}{4}\end{cases}}\)

=>\(\orbr{\begin{cases}x=\frac{2}{4}+\frac{3}{4}\\x=-\frac{2}{4}+\frac{3}{4}\end{cases}}\)

=>\(\orbr{\begin{cases}x=\frac{5}{4}\\x=\frac{1}{4}\end{cases}}\)

Vậy....

a) \(|x-\frac{3}{4}|=\frac{1}{2}\)

\(< =>\orbr{\begin{cases}x-\frac{3}{4}=\frac{1}{2}\\x-\frac{3}{4}=-\frac{1}{2}\end{cases}}\)

\(< =>\orbr{\begin{cases}x=\frac{1}{2}+\frac{3}{4}\\x=-\frac{1}{2}+\frac{3}{4}\end{cases}}\)

\(< =>\orbr{\begin{cases}x=\frac{5}{4}\\x=\frac{1}{4}\end{cases}}\)

Vay : x = 5/4 hoặc x =  1/4

b)\(saide\)

\(\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{4\cdot5}+...+\frac{1}{49\cdot50}\)

\(=\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{5}-.....+\frac{1}{49}-\frac{1}{50}\)

\(=\frac{1}{2}-\frac{1}{50}\)

\(=\frac{24}{50}=\frac{12}{25}\)

\(\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{4\cdot5}+...+\frac{1}{49\cdot50}\)

\(=\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{49}-\frac{1}{50}\)

\(=\frac{1}{2}-\frac{1}{50}\)

\(=\frac{12}{25}\)

Hình 6: REPEAT 6 [REPEAT 24 [FD 5 RT 15]RT 60]
Hình 4:REPEAT 4 [REPEAT 90 [FD 2 RT 2] RT 90] 
Tick cho mình nha

trả lời 

1/4.-3 (1/12+3/8)=-1,125

chúc bn 

hc tốt

trả lời

1/4.-3 (1/12+3/8)=-1,25

chúc bn 

hc tốt

-3/2 - 2x + 3/4 = -2

<=> -3/2 + (-2x) + 3/4 = -2

<=> (-2x) + (-3/2 + 3/4) = -2

<=> -2x + -3/4 = -2

<=> -2x = -2 + 3/4

<=> -2x = -5/4

<=> x = -5/4 : -2

<=> x = 5/8

=> x = 5/8

\(\frac{-3}{2}-2x+\frac{3}{4}=-2\)

\(< =>\frac{-3}{2}+\left(-2x\right)+\frac{3}{4}=-2\)

\(< =>\left(-2x\right)+\left(\frac{-3}{2}+\frac{3}{4}\right)=-2\)

\(< =>-2x+\frac{-3}{4}=-2\)

\(< =>-2x=-2+\frac{3}{4}\)

\(< =>-2x=\frac{-5}{4}\)

\(< =>x=\frac{-5}{4}:\left(-2\right)\)

\(< =>x=\frac{5}{8}\)

\(=>x=\frac{5}{8}\)