第43页

信息发布者:
B
$2$
$>$
$>$
解:
$|\sqrt[3]{-64}|-(-\sqrt{16})$
$=|-4|-(-4)$
$=4+4=8$
解:
$\sqrt{10^2}+4×\sqrt[3]{-\frac{1}{8}}+\sqrt{2}(\sqrt{2}-1)$
$=10+4×(-\frac{1}{2})+2-\sqrt{2}$
$=10-2+2-\sqrt{2}$
$=10-\sqrt{2}$
$2-\sqrt{2}$
解:(2)∵m+1=− ​$\sqrt {2}$​+2+1=− ​$\sqrt {2}$​+3>0,
m−1=− ​$\sqrt {2}$​+2−1=− ​$\sqrt {2}$​+1<0,
∴​$ |m+1|+$​{​$m−1|$​
=(−\sqrt 2+3)+( ​$\sqrt {2}$​−1)
=− ​$\sqrt {2}$​+3+\sqrt 2−1
​$=2. $​
 (3) ​$∵|2c + d|$​与​$\sqrt {d^2-16}$​互为相反数
​$∴|2c + d|+\sqrt {d^2-16}=0$​.
​$∴\begin {cases}2c + d = 0,\\d ^2-16 = 0.\end {cases}$​ 
​$∴\begin {cases}c = -2,\\d = 4\end {cases}$​
或​$\begin {cases}c = 2,\\d = -4.\end {cases}$​
当​$\begin {cases}c = -2,\\d = 4\end {cases}$​时,
​$2c - 3d = -16$​,无平方根.
当​$\begin {cases}c = 2,\\d = -4\end {cases}$​时,
​$2c - 3d = 16$​,平方根为​$\pm 4$​.
综上所述,当​$c = -2$​,​$d = 4$​时,​$2c - 3d$​无平方根;
当​$c = 2$​,​$d = -4$​时,​$2c - 3d$​的平方根为​$\pm 4$​.