2026年创优暑假作业七年级数学第28页答案
计算:
(1)$3\sqrt{6} +5\sqrt{6}$;
(2)$3\sqrt{2} +5\sqrt{2} -7\sqrt{2}$;
(3)$\sqrt{3} - (\sqrt{2} + \sqrt{3})$;
(4)$\sqrt{5} × (\sqrt{5} - \frac{1}{\sqrt{5}})$;
(5)$\sqrt{36} - \sqrt[3]{27} + \sqrt{(-2)^2}$;
(6)$2(\sqrt{2} +3\sqrt{5}) -3(2\sqrt{5} +2\sqrt{2})$;
(7)$-1^2 - |-\sqrt{2}| + \sqrt[3]{-8} + (\sqrt{2})^2$;
(8)$\sqrt[3]{27} - (\sqrt{3} - \sqrt{5}) - |\sqrt{5} - \sqrt{3}|$;
(9)$-\sqrt[3]{\frac{26}{27} -1} - \sqrt{1\frac{7}{9}} + \sqrt{0.25}$;
(10)$(-2)^2 × \sqrt{\frac{1}{64}} + \sqrt[3]{-27} + |\sqrt{2} -2|$;
(11)$|\sqrt{2} - \sqrt{6}| + |\sqrt{2} -1| - |\sqrt{6} -3|$;
(12)$(-2)^3 × \sqrt{(-4)^2} + \sqrt[3]{(-4)^3} × (\frac{1}{2})^2$;

答案

(1)原式=$(3+5)\sqrt{6}=8\sqrt{6}$;
(2)原式=$8\sqrt{2}-7\sqrt{2}=\sqrt{2}$;
(3)原式=$\sqrt{3}-\sqrt{2}-\sqrt{3}=-\sqrt{2}$;
(4)原式=$(\sqrt{5})^2-\sqrt{5}×\frac{1}{\sqrt{5}}=5-1=4$;
(5)原式=$6-3+2=5$;
(6)原式=$2\sqrt{2}+6\sqrt{5}-6\sqrt{5}-6\sqrt{2}=-4\sqrt{2}$;
(7)原式=$-1-\sqrt{2}+(-2)+2=-1-\sqrt{2}$;
(8)原式=$3-\sqrt{3}+\sqrt{5}-(\sqrt{5}-\sqrt{3})$
$=3-\sqrt{3}+\sqrt{5}-\sqrt{5}+\sqrt{3}=3$;
(9)原式=$\frac{1}{3}-\frac{4}{3}+0.5=-0.5$;
(10)原式=$4×\frac{1}{8}+(-3)+2-\sqrt{2}$
$=-\frac{1}{2}-\sqrt{2}$;
(11)原式=$\sqrt{6}-\sqrt{2}+\sqrt{2}-1-(3-\sqrt{6})$
$=\sqrt{6}-\sqrt{2}+\sqrt{2}-1-3+\sqrt{6}$
$=2\sqrt{6}-4$;
(12)原式=$-8×4+(-4)×\frac{1}{4}$
$=-32-1=-33$。