问题具体是：已知8*8 的FF矩阵，其中矩阵元素的公式和V84相同，此时求逆所用的内存大概是8GB。有没有办法，估计一个24*24 的矩阵FF888 \
（矩阵元素如U321的复杂度） 求逆所用的内存？因为原电脑8GB内存不够用，运行时总是算着算着就自动停止计算了。想要增加内存来计算，但是不知道具体大概要增加多少？
V84 = -cc2*f2*f2*Z14*Z14 +
2.0*cc1*f2*f2*Z14*
Z24 - (-4.0*bb2*bb2*bb1*AS + 1 bb2*bb2*cc1*f3 + cc2*cc1*cc1*f2 +
16.0*cc2*\[Nu]*AS*AS)*Z24*Z24;
FF = {{1, 0, Z11, 0, Z21, 0, U71, U81}, {0, 1, 0, Z11, 0, Z21, V71,
V81}, {1, 0, Z12, 0, Z22, 0, U72, U82}, {0, 1, 0, Z12, 0, Z22,
V72, V82}, {1, 0, Z13, 0, Z23, 0, U73, U83}, {0, 1, 0, Z13, 0,
Z23, V73, V83}, {1, 0, Z14, 0, Z24, 0, U74, U84}, {0, 1, 0, Z14,
0, Z24, V74, V84}};
FF4 = Inverse[FF];
U321 = (-c2*f1*f6*R*
R + ((cc1*cc2*cc3*V + cc1*cc1*c1*f5 + cc2*cc2*c2*f6 +
cc3*cc3*c3*f4 - 2.0*cc2*f6*V - c1*c2*c3)*
nu + (cc1*cc2*cc3*V + cc1*cc1*c1*f5 + cc2*cc2*c2*f6 +
cc3*cc3*c3*f4 - c2*f2*f6 - c1*c2*c3))*S*S -
c2*f3*f6*T*
T + (c3*g2*nu + 2.0*cc1*cc1*cc3*V + cc3*cc3*c3*f1 +
2.0*cc2*cc3*c2*f1 - cc1*cc1*c3*f3 - 2.0*c2*f1*f5 -
2.0*cc1*cc3*c2*f4 - c2*c2*c3)*R*S -
c2*(g2*nu + f6*f6 + f1*f3)*R*
T + (c1*g2*nu + 2.0*cc1*cc3*cc3*V + cc1*cc1*c1*f3 +
2.0*cc1*cc2*c2*f3 - cc3*cc3*c1*f1 - 2.0*c2*f3*f4 -
2.0*cc1*cc3*c2*f5 - c1*c2*c2)*S*T)/(Em*V); URST = R*S*T;
PF1 = {{1, 0, 0, R, 0, 0, S, 0, 0, T, 0, 0, U113, U114, U115, U116,
U117, U118, U119, U120, U121, URST, 0, 0}, {0, 1, 0, 0, R, 0, 0,
S, 0, 0, T, 0, U213, U214, U215, U216, U217, U218, U219, U220,
U221, 0, URST, 0}, {0, 0, 1, 0, 0, R, 0, 0, S, 0, 0, T, U313,
U314, U315, U316, U317, U318, U319, U320, U321, 0, 0, URST}};
FF888=Join[PF1, PF2, PF3, PF4, PF5, PF6, PF7, PF8];
FF8 = Inverse[FF888];

最直接的方法是统计2×2，3×3，4×4……的内存用量，看变化趋势。另，如果是要解线性方程的话，请不要使用矩阵求逆。