若(a3)m=a4•am,则m=______.
已知8x=2,8y=5,则8x+y=______.
(y-x)2n-1•(x-y)2n=______.
计算(-a3)4•(-a)3的结果是______ .
如图,AB∥CD.证明:∠B+∠F+∠D=∠E+∠G.
如图, ∠ABC+∠BCD+∠EDC=360°.求证:AB∥ED.
C