Question

B1, thực hiện phép tính ;

a, \(\frac{3}{-56}-\)\(\frac{-7}{64}\)

b, \(\frac{-5}{54}-\frac{11}{-36}\)

c, \(\frac{9}{28}+\)\(\frac{-2}{49}\)

d, \(\frac{-5}{-72}+\frac{7}{-48}\)

e, \(\frac{-5y}{2x^3}+\)\(\frac{2x}{3y}\)

f, \(\frac{2}{3x^4y^5}+\frac{5y^3}{2x^6}\)

Answer 1

\(a,\frac{3}{-56}-\frac{-7}{64}=\frac{-3.8}{448}+\frac{7.7}{448}=\frac{25}{448}\)

\(b,\frac{-5}{54}-\frac{11}{-36}=-\frac{5}{54}+\frac{11}{36}=\frac{-5.2}{108}+\frac{3.11}{108}=\frac{23}{108}\)

\(c,\frac{9}{28}+\frac{-2}{29}=\frac{9.29-2.28}{812}=\frac{205}{812}\)

\(d,\frac{-5}{-72}+\frac{7}{-48}=\frac{5}{72}-\frac{7}{48}=\frac{5.2-7.3}{144}=-\frac{11}{144}\)

\(e,\frac{-5y}{2x^3}+\frac{2x}{3y}=\frac{-5y.3y+2x.2x^3}{6x^3y}=\frac{-15y^2+4x^4}{6x^3y}\)

\(f,\frac{2}{3x^4y^5}+\frac{5y^3}{2x^6}=\frac{2.2x^2+5y^3.3y^5}{6x^6y^5}=\frac{4x^2+15y^8}{6x^6y^5}\)