2. (a)dy/dx=3/2x^2+8x-3,d2y/dx2=3x+8
(b) dy/dx=4x^3+3x^2-5x^(-2) , d2y/dx2=12x^2+6x+10x^(-3)
3.(a)dy/dx=4x-3, dy/dx|(1,1)=1
(b)dy/dx=1/2*(x^2-6x)^(-1/2)*(2x-6)=(x^2-6x)^(-1/2)*(x-3) ,dy/dx|(-2,4)= - 5/4
追问…第三题的B问看不懂…大神求详解
追答3(b). g(x)=(x^2-6x)^(1/2) , dg/dx=1/2*(x^2-6x)^(-1/2)*(2x-6)=(x^2-6x)^(-1/2)*(x-3),
上式中“^”之后括号内的数是表示指数。