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Help me answer this question please​

Help me answer this question please​-example-1

2 Answers

10 votes

Answer:

f''(x) ≈ 7953.87

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right

Algebra I

  • Factoring

Calculus

Derivatives

Basic Power Rule:

  • f(x) = cxⁿ
  • f’(x) = c·nxⁿ⁻¹

Product Rule:
\displaystyle (d)/(dx) [f(x)g(x)]=f'(x)g(x) + g'(x)f(x)

Derivative Rule:
\displaystyle (d)/(dx) [e^x]=e^x

Explanation:

Step 1: Define

f(x) = 4x³eˣ

f''(x) is x = 3 for 2nd Derivative

Step 2: Differentiate

  1. [1st Derivative] Product Rule [Basic Power Rule]: f'(x) = 3 · 4x³⁻¹eˣ + 4x³eˣ
  2. [1st Derivative] Simplify: f'(x) = 12x²eˣ + 4x³eˣ
  3. [1st Derivative] Factor: f'(x) = eˣ(12x² + 4x³)
  4. [2nd Derivative] Product Rule [Basic Power Rule]: f''(x) = eˣ(12x² + 4x³) + eˣ(2 · 12x²⁻¹ + 3 · 4x³⁻¹)
  5. [2nd Derivative] Simplify: f''(x) = eˣ(12x² + 4x³) + eˣ(24x + 12x²)
  6. [2nd Derivative] Distribute eˣ: f''(x) = 12eˣx² + 4eˣx³ + 24eˣx + 12eˣx²
  7. [2nd Derivative] Combine like terms: f''(x) = 24eˣx² + 4eˣx³ + 24eˣx
  8. [2nd Derivative] Factor: f''(x) = 4xeˣ(x² + 6x + 6)

Step 3: Evaluate

  1. Substitute: f''(x) = 4(3)e³(3² + 6(3) + 6)
  2. Exponents: f''(x) = 12e³(9 + 6(3) + 6)
  3. Multiply: f''(x) = 12e³(9 + 18 + 6)
  4. Add: f''(x) = 12e³(27 + 6)
  5. Add: f''(x) = 12e³(33)
  6. Multiply: f''(x) = 396e³
  7. Evaluate: f''(x) ≈ 396(20.0855)
  8. Multiply: f''(x) ≈ 7953.87
User Jianyongli
by
3.1k points
4 votes

9514 1404 393

Answer:

7953.873

Explanation:

The first derivative is ...

f'(x) = 4·3x²·e^x +4x³·e^x = e^x(4x³ +12x²)

Then the second derivative is ...

f''(x) = (12x² +24x)e^x +(4x³ +12x²)e^x

f''(x) = e^x(4x³ +24x² +24x)

So, f''(3) = (e^3)(4·27 +24·9 +24·3) = 396e^3 = 7953.87262158

Rounded to thousandths, this is ...

f''(3) = 7953.873

Help me answer this question please​-example-1
User Ben Newton
by
3.4k points