依题意得x2-x-2=0,解得x=2或-1,
∵x+1≠0,即x≠-1
∴x=2.
Because of Project Hope, _____ children have better lives. [ ]
A. thousand
B. thousands
C. Thousand of
D. thousands of
不同的水解糖方法各有优缺从整个过程来看()
A、酸解法所需时间最短
B、酸解法所需时间最长
C、霉解法时间最短
D、根据实际情况而定