设 , ,则(A-2E)-1=____。
求s=a+aa+aaa+…+aaa…aaa(n个a),其中a和n的值由用户自己输入。例如,当a=3,n=4时,S=3+33+333+3333。
A:=B+C;C://=A+B对于A存在()。
A free market is an economic system in which the price of goods and services is affected by supply and demand rather than controlled by a government. 这句话翻译成中文是()
If A= (x-y) -z and B=x- (y-z), then A-B= ______.
For all positive integers a and b, let (a|b)=(a-b)/(a+b) If m is a positive integer, what is (m|2m) ?
已知|a|=1,|b|=2。 (1)若a∥b,求a·b; (2)若a、b的夹角为60°,求|a+b|; (3)若a-b与a垂直,求当k为何值时,(ka-b)⊥(a+2b)。
The starting current of an a-cmotor is () the rated current.
设f(x)=|x-a|φ(x),而φ(x)在x=a处连续但不可导,则f(x)在x=a处( )。
The complete assembly of bedplate, A-frames and cylinder block is held together by () to form a rigid structure.