q=4t/(t^2+1),求dq/dt,谢

分类: 作业答案 • 2022-03-15 20:33:54

问题描述：

答

q=4t/(t^2+1)
q=[4(t^2+1)-4t*2t]/(t^2+1)^2
=4(-t^2+1)/(t^2+1)^2
=4(-t^2-1+2)/(t^2+1)^2
=-4/(t^2+1)+8/(t^2+1)^2