简化表达式

simplify 关键字使用代数、三角和指数函数恒等式简化表达式，并简化方根和乘方。

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• 要增加通过简化算法执行的步骤数，可添加修饰符 max。在某些情况下，与通过 simplify 自身简化相比，这会返回更加简化的结果。

• 要简化对某些变量的域进行假设的表达式，可使用要应用的假设在 simplify 后添加关键字 assume。

• 在简化它们之前要查看替换到位的数值的值，可使用 explicit 关键字。

• 如果要简化的表达式包含带有多个分支的函数 (例如平方根或反三角函数)，则 PTC Mathcad 返回的结果可能会在数值行为上与原始的结果不同。

• 使用关键字 combine 来简化涉及普通指数或对数的表达式：