1.-28×-28×-28+13×13×13+16×16×16
=21,952+2,197+4,096
=28,245.
2.12×12×12+-7×-7×-7+-5×-5×-5
=1,728+-343+-125
=1,260
→ 
→ 
![\sqrt{[(x_{2}-x_{1})^{2}+(y_{2}-y_{1})^{2}]}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B%28x_%7B2%7D-x_%7B1%7D%29%5E%7B2%7D%2B%28y_%7B2%7D-y_%7B1%7D%29%5E%7B2%7D%5D%7D%20)
![\sqrt{[(3-(-4))^{2}+(-1-(-5))^{2}]}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B%283-%28-4%29%29%5E%7B2%7D%2B%28-1-%28-5%29%29%5E%7B2%7D%5D%7D%20)
![\sqrt{[7^{2}+4^{2}]}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B7%5E%7B2%7D%2B4%5E%7B2%7D%5D%7D%20)
![\sqrt{[49+16]}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B49%2B16%5D%7D%20)
