Math Problem Statement

solve

Let h(x) = (x^3 + x + ln x)^{2x - x^2}. Determine the linearization of h at a = 1, and use it to approximate h(1.01). Suppose L(x) = 1 + 4x and M(x) = 7 - 2x are the linearizations of f and g, respectively, at a = 3. Determine the linearization of f/g at a = 3 and use it to approximate (f/g)(3.1).

Solution

Let's go through each part of this problem step-by-step.


Part (a): Let h(x)=(x3+x+lnx)2xx2h(x) = (x^3 + x + \ln x)^{2x - x^2}

(i) Determine the linearization of hh at a=1a = 1.

To find the linearization L(x)L(x) of h(x)h(x) at x=1x = 1, we use the formula: L(x)=h(1)+h(1)(x1)L(x) = h(1) + h'(1)(x - 1) So, we need to find h(1)h(1) and h(1)h'(1).

  1. Calculate h(1)h(1): Substitute x=1x = 1 into h(x)h(x): h(1)=(13+1+ln1)2112=(1+1+0)21=21=2h(1) = (1^3 + 1 + \ln 1)^{2 \cdot 1 - 1^2} = (1 + 1 + 0)^{2 - 1} = 2^1 = 2

  2. Calculate h(x)h'(x): Since h(x)=(x3+x+lnx)2xx2h(x) = (x^3 + x + \ln x)^{2x - x^2}, we use the logarithmic differentiation technique to differentiate.

    Let u(x)=x3+x+lnxu(x) = x^3 + x + \ln x and v(x)=2xx2v(x) = 2x - x^2. Then, h(x)=u(x)v(x)h(x) = u(x)^{v(x)} Taking the natural logarithm, lnh(x)=v(x)lnu(x)\ln h(x) = v(x) \ln u(x) Differentiating both sides with respect to xx: h(x)h(x)=v(x)lnu(x)+v(x)u(x)u(x)\frac{h'(x)}{h(x)} = v'(x) \ln u(x) + v(x) \frac{u'(x)}{u(x)} Solving this for h(x)h'(x) and evaluating at x=1x = 1 will yield h(1)h'(1).

(ii) Approximate h(1.01)h(1.01) using the linearization.

Using L(x)L(x) from part (i), substitute x=1.01x = 1.01 into L(x)L(x) to approximate h(1.01)h(1.01).


Part (b): Suppose L(x)=1+4xL(x) = 1 + 4x and M(x)=72xM(x) = 7 - 2x are the linearizations of ff and gg at a=3a = 3.

(i) Determine the linearization of fg\frac{f}{g} at a=3a = 3.

The linearization of fg\frac{f}{g} at x=3x = 3 can be found using the formula for the derivative of a quotient: (fg)=fgfgg2\left( \frac{f}{g} \right)' = \frac{f'g - fg'}{g^2} Using the values of f(3)f(3), f(3)f'(3), g(3)g(3), and g(3)g'(3) derived from L(x)L(x) and M(x)M(x), compute fg\frac{f}{g} at x=3x = 3.

(ii) Use the answer to (i) to approximate fg(3.1)\frac{f}{g}(3.1).

With the linearization found in (i), substitute x=3.1x = 3.1 to approximate fg(3.1)\frac{f}{g}(3.1).


Would you like detailed calculations for each derivative and linear approximation?

Related Questions

  1. How would you calculate h(x)h'(x) using implicit differentiation?
  2. Can you linearize a function with two variables, such as h(x,y)h(x, y)?
  3. What are the steps for finding higher-order approximations beyond linearization?
  4. How does linearization relate to Taylor series expansion?
  5. What are some applications of linear approximations in physics or engineering?

Tip

When working with exponential functions, logarithmic differentiation can simplify the process by allowing you to work with products instead of powers.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Linearization
Differentiation
Logarithmic Differentiation
Quotient Rule

Formulas

Linearization formula: L(x) = h(a) + h'(a)(x - a)
Quotient rule for derivatives: (f/g)' = (f'g - fg') / g^2

Theorems

Quotient Rule
Logarithmic Differentiation

Suitable Grade Level

Undergraduate Calculus