We know the answer but we don't know how to type in!!
更新1:
以指數記數法表示 a x b x (-b) x (-b) x (-a) x a x (-a) x (-b) 。 利用'^' 來輸入次方,如a的2次 x b的2次可輸入為a^2b^。
更新2:
sorry!! i forget la >,
更新3:
You must know that computer is very stupid, if the answer is not completely the same with it, it will say it wrong!!