Calculate $\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } }$ . $y = - 14 x ^ { 2 } + 15 x$
A) $- 7 x ^ { 3 } + 7.5 x ^ { 2 }$
B) $- 14 x ^ { 2 } + 15 x$
C) $- 7 x ^ { 3 } - 210 x ^ { 2 }$
D) $- 28$
E) $28 x$

Question

Calculate $\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } }$ .  $y = - 14 x ^ { 2 } + 15 x$  
A) $- 7 x ^ { 3 } + 7.5 x ^ { 2 }$
B) $- 14 x ^ { 2 } + 15 x$
C) $- 7 x ^ { 3 } - 210 x ^ { 2 }$
D) $- 28$
E) $28 x$

Quizplus · Accepted Answer

To find the second derivative of $y = - 14 x ^ { 2 } + 15 x$, we first differentiate it with respect to $x$ to get the first derivative, and then differentiate the result once more. The first derivative is $\frac{dy}{dx} = -28x + 15$, and the second derivative is $\frac{d^2y}{dx^2} = -28$.

Calculate d2y dx2\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } } dx2d2y​

Calculate $\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } }$