Math Problem Statement

If f(x) = 3x ^ 2 - x + 2 find f(2) f(- 2) f(a) f(- a) f(a + 1) 2f(a) f(2a) f(a ^ 2) [f(a)] ^ 2 and f(a + h)

Solution

Given the function f(x)=3x2x+2f(x) = 3x^2 - x + 2, let's calculate the values of each requested expression.

  1. Find f(2)f(2): f(2)=3(2)2(2)+2=3(4)2+2=122+2=12f(2) = 3(2)^2 - (2) + 2 = 3(4) - 2 + 2 = 12 - 2 + 2 = 12

  2. Find f(2)f(-2): f(2)=3(2)2(2)+2=3(4)+2+2=12+2+2=16f(-2) = 3(-2)^2 - (-2) + 2 = 3(4) + 2 + 2 = 12 + 2 + 2 = 16

  3. Find f(a)f(a): f(a)=3a2a+2f(a) = 3a^2 - a + 2

  4. Find f(a)f(-a): f(a)=3(a)2(a)+2=3a2+a+2f(-a) = 3(-a)^2 - (-a) + 2 = 3a^2 + a + 2

  5. Find f(a+1)f(a + 1): f(a+1)=3(a+1)2(a+1)+2f(a + 1) = 3(a + 1)^2 - (a + 1) + 2 First expand (a+1)2=a2+2a+1(a + 1)^2 = a^2 + 2a + 1: f(a+1)=3(a2+2a+1)(a+1)+2f(a + 1) = 3(a^2 + 2a + 1) - (a + 1) + 2 Now simplify: f(a+1)=3a2+6a+3a1+2=3a2+5a+4f(a + 1) = 3a^2 + 6a + 3 - a - 1 + 2 = 3a^2 + 5a + 4

  6. Find 2f(a)2f(a): 2f(a)=2(3a2a+2)=6a22a+42f(a) = 2(3a^2 - a + 2) = 6a^2 - 2a + 4

  7. Find f(2a)f(2a): f(2a)=3(2a)2(2a)+2=3(4a2)2a+2=12a22a+2f(2a) = 3(2a)^2 - (2a) + 2 = 3(4a^2) - 2a + 2 = 12a^2 - 2a + 2

  8. Find f(a2)f(a^2): f(a2)=3(a2)2a2+2=3a4a2+2f(a^2) = 3(a^2)^2 - a^2 + 2 = 3a^4 - a^2 + 2

  9. Find [f(a)]2[f(a)]^2: [f(a)]2=(3a2a+2)2[f(a)]^2 = (3a^2 - a + 2)^2 Expand: [f(a)]2=(3a2)22(3a2)(a)+2(3a2)(2)+(a)22(a)(2)+22[f(a)]^2 = (3a^2)^2 - 2(3a^2)(a) + 2(3a^2)(2) + (-a)^2 - 2(-a)(2) + 2^2 Simplify: [f(a)]2=9a46a3+12a2+a24a+4=9a46a3+13a24a+4[f(a)]^2 = 9a^4 - 6a^3 + 12a^2 + a^2 - 4a + 4 = 9a^4 - 6a^3 + 13a^2 - 4a + 4

  10. Find f(a+h)f(a + h): f(a+h)=3(a+h)2(a+h)+2f(a + h) = 3(a + h)^2 - (a + h) + 2 Expand (a+h)2=a2+2ah+h2(a + h)^2 = a^2 + 2ah + h^2: f(a+h)=3(a2+2ah+h2)(a+h)+2f(a + h) = 3(a^2 + 2ah + h^2) - (a + h) + 2 Now simplify: f(a+h)=3a2+6ah+3h2ah+2f(a + h) = 3a^2 + 6ah + 3h^2 - a - h + 2

Summary of Results:

  1. f(2)=12f(2) = 12
  2. f(2)=16f(-2) = 16
  3. f(a)=3a2a+2f(a) = 3a^2 - a + 2
  4. f(a)=3a2+a+2f(-a) = 3a^2 + a + 2
  5. f(a+1)=3a2+5a+4f(a + 1) = 3a^2 + 5a + 4
  6. 2f(a)=6a22a+42f(a) = 6a^2 - 2a + 4
  7. f(2a)=12a22a+2f(2a) = 12a^2 - 2a + 2
  8. f(a2)=3a4a2+2f(a^2) = 3a^4 - a^2 + 2
  9. [f(a)]2=9a46a3+13a24a+4[f(a)]^2 = 9a^4 - 6a^3 + 13a^2 - 4a + 4
  10. f(a+h)=3a2+6ah+3h2ah+2f(a + h) = 3a^2 + 6ah + 3h^2 - a - h + 2

Would you like any further details or clarifications on these calculations?


Follow-up Questions:

  1. How do you derive the formula for the square of a binomial, like in the case of f(a+1)f(a + 1)?
  2. Can you apply these techniques to find the derivative of f(x)f(x)?
  3. What happens if you plug specific values like a=1a = 1 or h=0h = 0 into these expressions?
  4. How would you solve for aa given that f(a)=0f(a) = 0?
  5. What are some other functions of the form f(x)=ax2+bx+cf(x) = ax^2 + bx + c and how do they behave differently?

Tip:

When expanding expressions like (a+h)2(a + h)^2, it's often helpful to first expand the square term and then simplify step by step. This method avoids mistakes and keeps calculations clear.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Functions
Algebra
Polynomial Functions
Substitution
Expansion

Formulas

f(x) = 3x^2 - x + 2
f(a) = 3a^2 - a + 2
f(-a) = 3a^2 + a + 2
f(a+1) = 3(a+1)^2 - (a+1) + 2
f(2a) = 12a^2 - 2a + 2
f(a^2) = 3a^4 - a^2 + 2
[f(a)]^2 = (3a^2 - a + 2)^2
f(a+h) = 3(a+h)^2 - (a+h) + 2

Theorems

Binomial Expansion
Function Composition

Suitable Grade Level

Grades 9-11