Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

(dy)/(dt)=2y, and 
y=8 when 
t=0.
Solve the equation.
Choose 1 answer:
(A) 
y=e^(8t)
(B) 
y=e^(2t)
(C) 
y=8e^(2t)
(D) 
y=2e^(8t)

dydt=2y \frac{d y}{d t}=2 y , and y=8 y=8 when t=0 t=0 .\newlineSolve the equation.\newlineChoose 11 answer:\newline(A) y=e8t y=e^{8 t} \newline(B) y=e2t y=e^{2 t} \newline(C) y=8e2t y=8 e^{2 t} \newline(D) y=2e8t y=2 e^{8 t}

Full solution

Q. dydt=2y \frac{d y}{d t}=2 y , and y=8 y=8 when t=0 t=0 .\newlineSolve the equation.\newlineChoose 11 answer:\newline(A) y=e8t y=e^{8 t} \newline(B) y=e2t y=e^{2 t} \newline(C) y=8e2t y=8 e^{2 t} \newline(D) y=2e8t y=2 e^{8 t}
  1. Recognize Linear Homogeneous Differential Equation: Recognize that the given differential equation is a first-order linear homogeneous differential equation which can be solved using separation of variables.
  2. Separate and Integrate Variables: Separate the variables by dividing both sides by yy and multiplying both sides by dtdt to get dyy=2dt\frac{dy}{y} = 2\, dt.
  3. Solve for Constant CC: Integrate both sides of the equation. The integral of 1y\frac{1}{y} dy is lny\ln|y|, and the integral of 22 dt is 2t2t. So, (1y)dy=2dt\int(\frac{1}{y}) dy = \int 2 dt leads to lny=2t+C\ln|y| = 2t + C, where CC is the constant of integration.
  4. Calculate Value of C: Solve for the constant CC using the initial condition y=8y=8 when t=0t=0. Plugging in the values, we get extln8=2imes0+C ext{ln}|8| = 2 imes 0 + C, which simplifies to extln(8)=C ext{ln}(8) = C.
  5. Substitute CC into Equation: Calculate the value of CC using the natural logarithm of 88.\newlineC=ln(8)=ln(23)=3ln(2)C = \ln(8) = \ln(2^3) = 3\ln(2).
  6. Exponentiate to Solve for y: Substitute the value of CC back into the equation lny=2t+C\ln|y| = 2t + C to get lny=2t+3ln(2)\ln|y| = 2t + 3\ln(2).
  7. Simplify Exponential Expression: Exponentiate both sides to solve for yy. We get y=e2t+3ln(2)|y| = e^{2t + 3\ln(2)}.
  8. Drop Absolute Value for Final Solution: Simplify the right side using properties of exponents. e3ln(2)e^{3\ln(2)} is the same as (eln(2))3(e^{\ln(2)})^3, which simplifies to 232^3 or 88. So, y=e2t×8|y| = e^{2t} \times 8.
  9. Drop Absolute Value for Final Solution: Simplify the right side using properties of exponents. e3ln(2)e^{3\ln(2)} is the same as (eln(2))3(e^{\ln(2)})^3, which simplifies to 232^3 or 88. So, y=e2t×8|y| = e^{2t} \times 8. Since yy is positive for t=0t=0 and y=8y=8, we can drop the absolute value to get y=8e2ty = 8e^{2t}.

More problems from Simplify rational expressions