a) Ta có: \(A=\dfrac{16^8-1}{\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)}\)

\(=\dfrac{2^{32}-1}{\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)}\)

\(=\dfrac{2^{32}-1}{\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)}\)

\(=\dfrac{2^{32}-1}{\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)}\)

\(=\dfrac{2^{32}-1}{\left(2^{16}-1\right)\left(2^{16}+1\right)}\)

\(=\dfrac{2^{32}-1}{2^{32}-1}=1\)

b) Ta có: \(B=\dfrac{\left(3+1\right)\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)}{9^{16}-1}\)

\(=\dfrac{\left(3^2-1\right)\cdot\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)}{2\cdot\left(3^{32}-1\right)}\)

\(=\dfrac{\left(3^4-1\right)\left(3^4+1\right)\left(3^8+1\right)\left(3^{16}+1\right)}{2\cdot\left(3^{32}-1\right)}\)

\(=\dfrac{\left(3^8-1\right)\left(3^8+1\right)\left(3^{16}+1\right)}{2\left(3^{32}-1\right)}\)

\(=\dfrac{\left(3^{16}-1\right)\left(3^{16}+1\right)}{2\left(3^{32}-1\right)}=\dfrac{1}{2}\)

= 36 đó bn

tich nha!!

1*2*4+2*4*8+4*8*16+8*16*32/1*3*4+2*6*8+4*12*16+8*24*32 = 56744

1*2*4+2*4*8+4*8*16+8*16*32/1*3*4+2*6*8+4*12*16+8*24*32 = 56744

#nhớ tk 

gfvfvfvfvfvfvfv555

\(1+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}\)

\(=\dfrac{5}{4}+\dfrac{1}{8}+\dfrac{1}{16}\)

\(=\dfrac{11}{8}+\dfrac{1}{16}\)

\(=\dfrac{23}{16}\)

______

\(2-\dfrac{1}{8}-\dfrac{1}{12}-\dfrac{1}{16}\)

\(=\dfrac{15}{8}-\dfrac{1}{12}-\dfrac{1}{16}\)

\(=\dfrac{43}{24}-\dfrac{1}{16}\)

\(=\dfrac{83}{48}\)

_________

\(\dfrac{4}{99}\times\dfrac{18}{5}:\dfrac{12}{11}+\dfrac{3}{5}\)

\(=\dfrac{8}{55}:\dfrac{12}{11}+\dfrac{3}{5}\)

\(=\dfrac{8}{55}\times\dfrac{11}{12}+\dfrac{3}{5}\)

\(=\dfrac{2}{15}+\dfrac{3}{5}\)

\(=\dfrac{11}{15}\)

__________

\(\left(1-\dfrac{3}{4}\right)\times\left(1+\dfrac{1}{3}\right)\times\left(1-\dfrac{1}{3}\right)\)

\(=\dfrac{1}{4}\times\dfrac{4}{3}\times\dfrac{2}{3}\)

\(=\dfrac{4\times2}{4\times3\times3}\)

\(=\dfrac{2}{3\times3}\)

\(=\dfrac{2}{9}\)

Bài làm

\(\frac{\left(1+\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)}{\left(1-\frac{1}{2}+\frac{1}{4}-\frac{1}{8}+\frac{1}{16}\right)}\)

\(=\frac{\left(\frac{2}{2}+\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+\frac{1}{2^4}\right)}{\left(\frac{2}{2}-\frac{1}{2}+\frac{1}{2^2}-\frac{1}{2^3}+\frac{1}{2^4}\right)}\)

\(=\frac{\frac{1}{2}\left(2+1+\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}\right)}{\frac{1}{2}\left(2-1+\frac{1}{2}-\frac{1}{2^2}+\frac{1}{2^3}\right)}\)

\(=\frac{3+\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}}{1+\frac{1}{2}-\frac{1}{2^2}+\frac{1}{2^3}}\)

\(=\frac{\frac{24}{8}+\frac{4}{8}+\frac{2}{8}+\frac{1}{8}}{\frac{8}{8}+\frac{4}{8}-\frac{2}{8}+\frac{1}{8}}\)

\(=\frac{31}{8}\div\frac{11}{8}\)

\(=\frac{31}{8}\cdot\frac{8}{11}\)

\(=\frac{31}{11}\)

P/S: Trông không thuận tiện lắm :/

Hawy tính giúp mình nha mình cho đúng

Hơi căng 

\(\frac{\left(1+\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)}{\left(1-\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}\right)}=\frac{\left(\frac{16}{16}+\frac{8}{16}+\frac{4}{16}+\frac{2}{16}+\frac{1}{16}\right)}{\left(\frac{16}{16}-\frac{8}{16}+\frac{4}{16}+\frac{2}{16}+\frac{1}{16}\right)}=\frac{\frac{31}{16}}{\frac{15}{16}}=\frac{31}{16}:\frac{15}{16}=\frac{31}{16}\times\frac{16}{15}=\frac{31}{15}\)

nhầm gì đúng đề mà 

1+1=2  ;2+2=4  ;4+4=8  ;8+8=16  ;16+16=32

1+1=2

2+2=4

4+4=8

8+8=16

16+16=32

có giỏi thì mét  cô đi

\(=\dfrac{1+x+1-x}{1-x^2}+\dfrac{2}{1+x^2}+...+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{2}{1-x^2}+\dfrac{2}{1+x^2}+...+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{2+2x^2+2-2x^2}{1-x^4}+...+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{4}{1-x^4}+\dfrac{4}{1+x^4}+\dfrac{8}{1+x^8}+...+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{4+4x^4+4-4x^4}{1-x^8}+\dfrac{8}{1+x^8}+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{8+8x^8+8-8x^8}{1-x^{16}}+\dfrac{16}{1+x^{16}}\)

\(=\dfrac{16+16x^{16}+16-16x^{16}}{1-x^{32}}=\dfrac{32}{1-x^{32}}\)