dx/dt=2*t-1;求x=x(t)?

dx/(x+t)=dt dx/dt=2*t-1;求x=x(t)? 求d/dx (∫[0,x](根号(1+t^2)dt)=? y= ∫[0,x](t-1)^3(t-2)dt,dy/dx(x=0) 设f(t)=∫e^(-x^2)dx,求∫tf(t)dt=? dx/dt=x+t,dy/dt=-y+t,求x,y(t为常数）. dx=(x+t–1)dt怎么积分? 定积分，f(x)=∫(1,x^2)e^-t^2dt,求 ∫(0,1)xf(x)dx 设f(x)=∫【x,1】((e)^(-t^2)）dt,求∫【1,0】f(x）dx f(x)=∫（x^2,1）sint/t dt,求∫(1,0)xf(x)dx f(x)=∫(0,x^2) e^(-t^2)dt,求∫(0,1)xf(x)dx 求解dx/(x+t)=dy/(-y+t)=dt