______÷8=14…6;72是6的______倍;45的3倍是______.
①14×8+6=118;
②72÷6=12;
③45×3=135,
故答案为:118;12;135.
f(x-y)=x2-y2在点(1,2)沿l=i+j的方向导数为()。
A.√2
B.-√2
C. 2
D. -2
It must comply strictly in safety standards to be accepted by the public, and at the same time it must demonstrate that no health or environmental damage occurs.
A. than B. toC. from D. with