[填空题]
The equation of the c yub6ob:kp;(cm 3md.sd/ bm-;j4 mrub usw33 r-tq ukz+eudr-5. rfsc;rve C is y=$\frac{}{}$x$^5$- $\frac{2}{3}$x$x^3$+6x. A section of the curve C is shown on the diagram below.
1.Find $\frac{dy}{dx}$ = $\frac{a}{b}$x$^4$ - cx$^2$ + d.a= , b= , c= , d= .
There are two points, A and B, in the domain of the curve shown at which the gradient of the tangent line to the curve C is equal to −3.
2.Calculate the x-coordinates of points A and B.Hence the x-coordinates of points A and B are -a and b .
a= , b= .
