Question

这道物理题怎么做

Answer 1

根据V²-V0²=2ax V0=0
a=2+6x²
得V²=2*（2+6x²）x=4x+12x³
V=√（4x+12x³）

Answer 2

a = dv/dt = dv/dx * dx/dt = v dv/dx
所以 v dv/dx = 2 + 6x^2
分离变量 v dv = (2 + 6x^2)dx
积分 ∫(0→v) v dv = ∫(0→x) (2 + 6x^2)dx
1/2 v^2 = 2x + 2x^3
v = 2 ( x + x^3)^(1/2)