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Suppose a,b,c,gt 1 and f(x)=|(a^(-x),a...

Suppose `a,b,c,gt 1` and
`f(x)=|(a^(-x),a^(x),x),(b^(-3x),b^(3x),3x^(3)),(c^(-5x),c^(5x),5x^(5))|, x epsilon R` then f is

A

a constant function

B

a polynomial of degree 5

C

an odd function

D

an even funtion

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To solve the problem, we need to evaluate the determinant given by the function \( f(x) \): \[ f(x) = \begin{vmatrix} a^{-x} & a^{x} & x \\ b^{-3x} & b^{3x} & 3x^{3} \\ c^{-5x} & c^{5x} & 5x^{5} \end{vmatrix} \] ### Step 1: Calculate the Determinant We will calculate the determinant using the formula for a 3x3 matrix: \[ \text{det}(A) = a(ei - fh) - b(di - fg) + c(dh - eg) \] For our matrix: - \( a = a^{-x} \), \( b = a^{x} \), \( c = x \) - \( d = b^{-3x} \), \( e = b^{3x} \), \( f = 3x^{3} \) - \( g = c^{-5x} \), \( h = c^{5x} \), \( i = 5x^{5} \) Thus, we can express the determinant as: \[ f(x) = a^{-x} \left( b^{3x} \cdot 5x^{5} - 3x^{3} \cdot c^{5x} \right) - a^{x} \left( b^{-3x} \cdot 5x^{5} - 3x^{3} \cdot c^{-5x} \right) + x \left( b^{-3x} \cdot c^{5x} - b^{3x} \cdot c^{-5x} \right) \] ### Step 2: Simplifying the Determinant Now we will simplify each term in the determinant: 1. **First Term:** \[ a^{-x} \left( b^{3x} \cdot 5x^{5} - 3x^{3} \cdot c^{5x} \right) \] 2. **Second Term:** \[ - a^{x} \left( b^{-3x} \cdot 5x^{5} - 3x^{3} \cdot c^{-5x} \right) \] 3. **Third Term:** \[ + x \left( b^{-3x} \cdot c^{5x} - b^{3x} \cdot c^{-5x} \right) \] ### Step 3: Combine and Factor Now we can combine the terms and factor out common elements where possible. The expression becomes: \[ f(x) = a^{-x} b^{3x} \cdot 5x^{5} - a^{-x} 3x^{3} c^{5x} - a^{x} b^{-3x} \cdot 5x^{5} + a^{x} 3x^{3} c^{-5x} + x (b^{-3x} c^{5x} - b^{3x} c^{-5x}) \] ### Step 4: Determine the Nature of \( f(x) \) Now we need to analyze \( f(x) \) to determine its properties: 1. **Check if \( f(x) \) is a constant function:** Since \( f(x) \) contains terms with \( x \) raised to various powers, it is not a constant function. 2. **Check if \( f(x) \) is a polynomial function:** The highest degree term in \( f(x) \) is \( 5x^{5} \), indicating that \( f(x) \) is indeed a polynomial of degree 5. 3. **Check if \( f(x) \) is even or odd:** To check if \( f(x) \) is even or odd, we compute \( f(-x) \) and compare it to \( f(x) \): - If \( f(-x) = f(x) \), then \( f(x) \) is even. - If \( f(-x) = -f(x) \), then \( f(x) \) is odd. After performing the calculations, we find that \( f(-x) = f(x) \), confirming that \( f(x) \) is an even function. ### Final Conclusion Thus, we conclude that: - \( f(x) \) is a polynomial of degree 5. - \( f(x) \) is an even function.
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MCGROW HILL PUBLICATION-DETERMINANTS-SOLVED EXAMPLES (LEVEL 1 SINGLE CORRECT ANSWER TYPE QUESTIONS)
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  3. Suppose a,b,c,gt 1 and f(x)=|(a^(-x),a^(x),x),(b^(-3x),b^(3x),3x^(3)...

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  4. Suppose n,m are natural numbers and f(x)=|(1,(1+x)^(m),(1+mx)^(mn)),...

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  5. Suppose a,b,c are sides of a scalene triangle. Let Delta=|(a,b,c),(b...

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  6. If A,B and C are angle of a triangle of a triangle ,the value of |{:(...

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  10. Prove that |{:(1, a, a^(2)-bc),(1, b, b^(2)-ca), (1, c, c^(2)-ab):}|=...

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  14. If 1,omega , omega^2 are the cube roots of unity , then Delta=|(1,ome...

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  15. Using properties of determinants, prove that |b+c q+r y+z c+a r+p ...

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