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Factorise the expression f(x)=2x^(3)-7x^...

Factorise the expression `f(x)=2x^(3)-7x^(2)-3x+18`,
Hence, find all possible values of x for which f(x)=0.

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To factorize the expression \( f(x) = 2x^3 - 7x^2 - 3x + 18 \) and find all possible values of \( x \) for which \( f(x) = 0 \), we can follow these steps: ### Step 1: Rearranging the expression We start with the polynomial: \[ f(x) = 2x^3 - 7x^2 - 3x + 18 \] ### Step 2: Grouping terms We can rearrange and group the terms in a way that makes it easier to factor: \[ f(x) = 2x^3 - 4x^2 - 3x^2 + 6x - 6x + 18 \] This does not change the expression but helps us to factor by grouping. ### Step 3: Factoring by grouping Now, we can group the terms: \[ = (2x^3 - 4x^2) + (-3x^2 + 6x) + (-6x + 18) \] Factoring out common terms from each group: \[ = 2x^2(x - 2) - 3(x^2 - 6) \] ### Step 4: Factoring further Next, we can factor out \( x - 2 \): \[ = (x - 2)(2x^2 - 3x - 9) \] ### Step 5: Factoring the quadratic Now we need to factor the quadratic \( 2x^2 - 3x - 9 \). We look for two numbers that multiply to \( 2 \times -9 = -18 \) and add to \( -3 \). The numbers are \( 3 \) and \( -6 \): \[ = 2x^2 + 3x - 6x - 9 \] Grouping again: \[ = (2x^2 + 3x) + (-6x - 9) \] Factoring out common terms: \[ = x(2x + 3) - 3(2x + 3) \] Thus, \[ = (x - 3)(2x + 3) \] ### Step 6: Final factorization Putting it all together, we have: \[ f(x) = (x - 2)(2x + 3)(x - 3) \] ### Step 7: Finding the roots To find the values of \( x \) for which \( f(x) = 0 \), we set each factor to zero: 1. \( x - 2 = 0 \) → \( x = 2 \) 2. \( 2x + 3 = 0 \) → \( 2x = -3 \) → \( x = -\frac{3}{2} \) 3. \( x - 3 = 0 \) → \( x = 3 \) ### Step 8: Listing all possible values The possible values of \( x \) for which \( f(x) = 0 \) are: - \( x = 2 \) - \( x = -\frac{3}{2} \) - \( x = 3 \) ### Final Answer The possible values of \( x \) for which \( f(x) = 0 \) are \( 2, -\frac{3}{2}, \) and \( 3 \). ---
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