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Math hw for tonight
help solve this problem! Thank you!
ap cal bc

Math hw for tonight help solve this problem! Thank you! ap cal bc-example-1
User Ken Shih
by
7.9k points

2 Answers

1 vote

Answer:

2t + 4

Explanation:

A parametric equation is one where x and y are defined separately in terms of a third variable (often the parameter t).

To find dy/dx from parametric equations, differentiate each equation with respect to the parameter t, then use the chain rule:


\boxed{\frac{\text{d}y}{\text{d}x}=\frac{\text{d}y}{\text{d}t} * \frac{\text{d}t}{\text{d}x}}

Differentiate the two parametric equations with respect to t:


x=t-3 \implies \frac{\text{d}x}{\text{d}t}=1


y=t^2+4t \implies \frac{\text{d}y}{\text{d}t}=2t+4

Use the chain rule to combine them:


\begin{aligned}\implies \frac{\text{d}y}{\text{d}x}&=\frac{\text{d}y}{\text{d}t} * \frac{\text{d}t}{\text{d}x}\\\\&=(2t+4) * (1)/(1)\\\\&=2t+4\end{aligned}

Therefore:


\boxed{\frac{\text{d}y}{\text{d}x}=2t+4}

User Pawel Stolowski
by
7.5k points
2 votes

Answer:

first option

Explanation:

differentiate using the power rule


(d)/(dx) (a
x^(n) ) = na
x^(n-1)

then


(dy)/(dx) =
(dy)/(dt) ×
(dt)/(dx) =
((dy)/(dt) )/((dx)/(dt) )

y = t² + 4t


(dy)/(dt) = 2t + 4

x = t - 3


(dx)/(dt) = 1

then


(dy)/(dx) =
(2t+4)/(1) = 2t + 4

User Niko Jojo
by
7.5k points