抱歉,我找不到任何东西。
如果我有带符号函数f(x)的表达式,现在我想用其显式形式替换这些表达式f(x)怎么做?
例如:
我有
f(x):= x^2+sin(x)
和区别
diff (%e**sqrt(f(x)*a), x,2);
我现在要用上面的表达式替换f(x)
吗?
谢谢
卡尔
(%i1) i: integrate(f(x)*f(4*x), x, 0, 1) $
(%i2) f(x):= x^2+sin(x) $
(%i3) ev(i, f);
1
/
[ 2 2
(%o3) I (sin(x) + x ) (sin(4 x) + 16 x ) dx
]
/
0
-- Function: ev (<expr>, <arg_1>, ..., <arg_n>) Evaluates the expression <expr> in the environment specified by the arguments <arg_1>, ..., <arg_n>. The arguments are switches (Boolean flags), assignments, equations, and functions. 'ev' returns the result (another expression) of the evaluation.