Question

Hãy tính hợp lý:

    A=(1/3 - 8/15 - 1/7) + ( 2/3 - (-7/15) + 8/7)

    B=(0,25 + 3/5 - (1/8 - 2/5 +5/4)

 

Mn giúp mik nha________mik mơn nhìu>.<

Answer 1

\(A=\left(\frac{1}{3}-\frac{8}{15}-\frac{1}{7}\right)+\left[\frac{2}{3}-\left(-\frac{7}{15}\right)+\frac{8}{7}\right]\)

\(A=\frac{1}{3}-\frac{8}{15}-\frac{1}{7}+\frac{2}{3}+\frac{7}{15}+\frac{8}{7}\)

\(A=\left(\frac{1}{3}+\frac{2}{3}\right)+\left(-\frac{8}{15}+\frac{7}{15}\right)+\left(-\frac{1}{7}+\frac{8}{7}\right)\)

\(A=1+\left(-\frac{1}{15}\right)+1\)

\(A=\frac{29}{15}\)

\(B=\left[\left(0,25+\frac{3}{5}\right)-\left(\frac{1}{8}-\frac{2}{5}+\frac{5}{4}\right)\right]\)

\(B=\frac{1}{4}+\frac{3}{5}-\frac{1}{8}+\frac{2}{5}-\frac{5}{4}\)

\(B=\left(\frac{1}{4}-\frac{5}{4}\right)+\left(\frac{3}{5}+\frac{2}{5}\right)-\frac{1}{8}\)

\(B=-1+1-\frac{1}{8}\)

\(B=0-\frac{1}{8}\)
\(B=-\frac{1}{8}\)

Answer 2

\(=\frac{1}{3}-\frac{8}{15}-\frac{1}{7}+\frac{2}{3}+\frac{7}{15}+\frac{8}{7}\)

\(=\left(\frac{1}{3}+\frac{2}{3}\right)-\left(\frac{8}{15}+\frac{7}{15}\right)-\left(\frac{1}{7}-\frac{8}{7}\right)\)

\(=1-1+1\)

\(=0\)

Answer 3

\(A=\left(\frac{1}{3}-\frac{8}{15}-\frac{1}{7}\right)+\left(\frac{2}{3}-\left(-\frac{7}{15}\right)+\frac{8}{7}\right)\)

\(A=\frac{1}{3}-\frac{8}{15}-\frac{1}{7}+\frac{2}{3}+\frac{7}{15}+\frac{8}{7}\)

\(A=\left(\frac{1}{3}+\frac{2}{3}\right)-\left(\frac{8}{15}-\frac{7}{15}\right)+\left(\frac{8}{7}-\frac{1}{7}\right)\)

\(A=1-\frac{1}{15}+1\)

\(A=\frac{29}{15}\)

\(B=\left[0,25+\frac{3}{5}-\left(\frac{1}{8}-\frac{2}{5}+\frac{5}{4}\right)\right]\)

\(B=\left[\frac{1}{4}+\frac{3}{5}-\frac{1}{8}+\frac{2}{5}-\frac{5}{4}\right]\)

\(B=\left(\frac{1}{4}-\frac{5}{4}\right)+\left(\frac{3}{5}+\frac{2}{5}\right)-\frac{1}{8}\)

\(B=\left(-1\right)+1-\frac{1}{8}\)

\(B=0-\frac{1}{8}\)

\(B=-\frac{1}{8}\)

Answer 4

\(B\)\(=\)\(-\)\(\frac{1}{8}\)

Tk mk nhé

Thanks everyone

Answer 5

B = \(-\)\(\frac{1}{8}\)

~ Ủng hộ nha ~

Thanks nhìu