设参数方程,确定了y是x的函数,f″(t)存在且不为零,则d2y/d2x的值是:()
A: -1/f″(t)
B: 1/[f″(t)]2
C: -1/[f″(t)]2
D: 1/f″(t)
A: -1/f″(t)
B: 1/[f″(t)]2
C: -1/[f″(t)]2
D: 1/f″(t)
举一反三
- 设参数方程,确定了y是x的函数,f″(t)存在且不为零,则d2y/d2x的值是:() A: -1/f″(t) B: 1/[f″(t)] C: -1/[f″(t)] D: 1/f″(t)
- 【多选题】若f 1 (t) = ɛ (-t) , f 2 (t) = e t ,则f 1 (t)* f 2 (t) = A. f 1 ꞌ (t)* f 2 (–1) (t) B. f 1 (–1) (t)* f 2 ꞌ (t) C. f 1 (t-3)* f 2 (t+3) D. f 1 (–3) (t)* f 2 ꞌꞌꞌ (t)
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