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Suppose a in R. Define f and g as follow...

Suppose `a in R`. Define f and g as follows:
`f(x) =(a^(2) - 4a + 3)x^(2) + (a^(2) -1)a AA x in R` and `g(x) = (a^(2) - 5a + 6)x^(3) + (a^(2) -3a+ 2)x + (a^(3) -1) AA x in R`
The number of values of a for which `f(x) = g(x) AA x in R`

A

0

B

1

C

2

D

infinite

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the number of values of \( a \) for which the functions \( f(x) \) and \( g(x) \) are equal for all \( x \in \mathbb{R} \). ### Step 1: Write down the functions The functions are defined as: \[ f(x) = (a^2 - 4a + 3)x^2 + (a^2 - 1)a \] \[ g(x) = (a^2 - 5a + 6)x^3 + (a^2 - 3a + 2)x + (a^3 - 1) \] ### Step 2: Set the functions equal to each other We need to set \( f(x) = g(x) \): \[ (a^2 - 4a + 3)x^2 + (a^2 - 1)a = (a^2 - 5a + 6)x^3 + (a^2 - 3a + 2)x + (a^3 - 1) \] ### Step 3: Rearranging the equation Rearranging gives us: \[ 0 = (a^2 - 5a + 6)x^3 + (a^2 - 3a + 2)x + (a^3 - 1) - (a^2 - 4a + 3)x^2 - (a^2 - 1)a \] ### Step 4: Group terms by powers of \( x \) Now we will group the terms by the powers of \( x \): - Coefficient of \( x^3 \): \( a^2 - 5a + 6 \) - Coefficient of \( x^2 \): \( -(a^2 - 4a + 3) \) - Coefficient of \( x \): \( a^2 - 3a + 2 \) - Constant term: \( a^3 - 1 - (a^2 - 1)a \) ### Step 5: Set coefficients equal to zero For \( f(x) \) and \( g(x) \) to be equal for all \( x \), each coefficient must be equal to zero: 1. \( a^2 - 5a + 6 = 0 \) 2. \( -(a^2 - 4a + 3) = 0 \) 3. \( a^2 - 3a + 2 = 0 \) 4. \( a^3 - 1 - (a^2 - 1)a = 0 \) ### Step 6: Solve each equation 1. **From \( a^2 - 5a + 6 = 0 \)**: \[ (a - 2)(a - 3) = 0 \implies a = 2 \text{ or } a = 3 \] 2. **From \( -(a^2 - 4a + 3) = 0 \)**: \[ a^2 - 4a + 3 = 0 \implies (a - 1)(a - 3) = 0 \implies a = 1 \text{ or } a = 3 \] 3. **From \( a^2 - 3a + 2 = 0 \)**: \[ (a - 1)(a - 2) = 0 \implies a = 1 \text{ or } a = 2 \] 4. **From \( a^3 - 1 - (a^2 - 1)a = 0 \)**: \[ a^3 - 1 - a^3 + a = 0 \implies a - 1 = 0 \implies a = 1 \] ### Step 7: Combine solutions The possible values of \( a \) from all equations are: - From the first equation: \( 2, 3 \) - From the second equation: \( 1, 3 \) - From the third equation: \( 1, 2 \) - From the fourth equation: \( 1 \) The unique values of \( a \) that satisfy all equations are \( 1, 2, 3 \). ### Conclusion Thus, the number of values of \( a \) for which \( f(x) = g(x) \) for all \( x \in \mathbb{R} \) is **3**. ---
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MCGROW HILL PUBLICATION-SETS, RELATIONS AND FUNCTIONS-EXERCISE ( LEVEL 2 (SINGLE CORRECT ANSWER TYPE QUESTIONS ))
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