數(shù)學(xué)計(jì)算代入題目及答案1.計(jì)算\(\frac{1}{2}\times4\)的結(jié)果。答案：\(\frac{1}{2}\times4=2\)。2.計(jì)算\(3x+2y=10\)當(dāng)\(x=2\)和\(y=1\)時(shí)的值。答案：將\(x=2\)和\(y=1\)代入方程\(3x+2y=10\)，得到\(3\times2+2\times1=6+2=8\)。3.計(jì)算\(5a-3b=12\)當(dāng)\(a=3\)和\(b=1\)時(shí)的值。答案：將\(a=3\)和\(b=1\)代入方程\(5a-3b=12\)，得到\(5\times3-3\times1=15-3=12\)。4.計(jì)算\((x+2)^2\)當(dāng)\(x=4\)時(shí)的值。答案：將\(x=4\)代入\((x+2)^2\)，得到\((4+2)^2=6^2=36\)。5.計(jì)算\(\sqrt{9}\)的值。答案：\(\sqrt{9}=3\)。6.計(jì)算\(\frac{3}{4}\div\frac{3}{2}\)的結(jié)果。答案：\(\frac{3}{4}\div\frac{3}{2}=\frac{3}{4}\times\frac{2}{3}=\frac{1}{2}\)。7.計(jì)算\(2^3\times3^2\)的結(jié)果。答案：\(2^3\times3^2=8\times9=72\)。8.計(jì)算\(\frac{1}{x}+\frac{1}{y}=\frac{5}{6}\)當(dāng)\(x=2\)和\(y=3\)時(shí)的值。答案：將\(x=2\)和\(y=3\)代入方程\(\frac{1}{x}+\frac{1}{y}=\frac{5}{6}\)，得到\(\frac{1}{2}+\frac{1}{3}=\frac{3}{6}+\frac{2}{6}=\frac{5}{6}\)。9.計(jì)算\((x-3)(x+3)\)當(dāng)\(x=5\)時(shí)的值。答案：將\(x=5\)代入\((x-3)(x+3)\)，得到\((5-3)(5+3)=2\times8=16\)。10.計(jì)算\(\sqrt[3]{27}\)的值。答案：\(\sqrt[3]{27}=3\)。11.計(jì)算\(\frac{2x+3}{x-1}=5\)當(dāng)\(x=4\)時(shí)的值。答案：將\(x=4\)代入方程\(\frac{2x+3}{x-1}=5\)，得到\(\frac{2\times4+3}{4-1}=\frac{8+3}{3}=\frac{11}{3}=5\)。12.計(jì)算\(\frac{1}{2}\times\frac{3}{4}\times\frac{4}{5}\)的結(jié)果。答案：\(\frac{1}{2}\times\frac{3}{4}\times\frac{4}{5}=\frac{3}{10}\)。13.計(jì)算\((x+1)(x-1)=x^2-1\)當(dāng)\(x=6\)時(shí)的值。答案：將\(x=6\)代入\((x+1)(x-1)=x^2-1\)，得到\((6+1)(6-1)=7\times5=35\)，而\(x^2-1=6^2-1=36-1=35\)。14.計(jì)算\(\sqrt{49}\)的值。答案：\(\sqrt{49}=7\)。15.計(jì)算\(\frac{5}{8}-\frac{1}{4}\)的結(jié)果。答案：\(\frac{5}{8}-\frac{1}{4}=\frac{5}{8}-\frac{2}{8}=\frac{3}{8}\)。16.計(jì)算\(2^4\div2^2\)的結(jié)果。答案：\(2^4\div2^2=2^{4-2}=2^2=4\)。17.計(jì)算\(\frac{3}{7}\times\frac{7}{3}=1\)的結(jié)果。答案：\(\frac{3}{7}\times\frac{7}{3}=1\)。18.計(jì)算\(\sqrt{144}\)的值。答案：\(\sqrt{144}=12\)。19.計(jì)算\(\frac{4}{5}+\frac{1}{5}\)的結(jié)果。答案：\(\frac{4}{5}+\frac{1}{5}=\frac{5}{