Bỏ dấu ngoặc rồi tính

- Hướng dẫn giải

$$\begin{gathered} \begin{array}{l}a)159-524-\left(59-424\right);\\ =159-524-59+424\\ =\left(159-59\right)-\left(524-424\right)\\ =100-100\\ =0\end{array} \\ \begin{array}{l}b)\left(36+79\right)+\left(145-79-36\right);\\ =36+79+145-79-36\\ =\left(36-36\right)+\left(79-79\right)+145\\ =145\end{array} \\ \begin{array}{l}c)334-\left(117+234\right)+\left(42+117\right);\\ =334-117-234+42+117\\ =\left(334-234\right)-\left(117-117\right)+42\\ =100+42\\ =142\end{array} \\ \begin{array}{l}d)271-\left[\left(-43\right)+271-\left(-17\right)\right].\\ =271-\left[-43+271+17\right]\\ =271+43-271-17\\ =\left(271-271\right)+\left(43-17\right)\\ =26\end{array} \end{gathered}$$