Get expert advice and insights on any topic with IDNLearn.com. Get timely and accurate answers to your questions from our dedicated community of experts who are here to help you.

12. Given the function [tex]$f(x) = x^3 - x$[/tex], simplify the following expression:

[tex]\frac{f(x) - f(1)}{x - 1}[/tex]


Sagot :

Sure, let's go step-by-step to solve the problem.

The function given is:

[tex]\[ f(x) = x^3 - x \][/tex]

Step 1: Evaluate [tex]\( f(1) \)[/tex]

First, we need to find [tex]\( f(1) \)[/tex]:

[tex]\[ f(1) = 1^3 - 1 = 1 - 1 = 0 \][/tex]

So, [tex]\( f(1) = 0 \)[/tex].

Step 2: Substitute [tex]\( f(1) \)[/tex] and simplify the expression

Now, we need to compute the expression:

[tex]\[ \frac{f(x) - f(1)}{x - 1} \][/tex]

Substitute [tex]\( f(x) = x^3 - x \)[/tex] and [tex]\( f(1) = 0 \)[/tex]:

[tex]\[ \frac{f(x) - f(1)}{x - 1} = \frac{(x^3 - x) - 0}{x - 1} = \frac{x^3 - x}{x - 1} \][/tex]

Step 3: Simplify the quotient

We now need to simplify the expression [tex]\( \frac{x^3 - x}{x - 1} \)[/tex].

Notice that [tex]\( x^3 - x \)[/tex] can be factored:

[tex]\[ x^3 - x = x(x^2 - 1) \][/tex]

And further factorizing [tex]\( x^2 - 1 \)[/tex]:

[tex]\[ x^2 - 1 = (x - 1)(x + 1) \][/tex]

So:

[tex]\[ x^3 - x = x(x - 1)(x + 1) \][/tex]

Thus, we can write:

[tex]\[ \frac{x^3 - x}{x - 1} = \frac{x(x - 1)(x + 1)}{x - 1} \][/tex]

Since [tex]\( x \neq 1 \)[/tex], we can cancel out [tex]\( x - 1 \)[/tex] in the numerator and denominator:

[tex]\[ \frac{x(x - 1)(x + 1)}{x - 1} = x(x + 1) \][/tex]

So, the simplified form is:

[tex]\[ \frac{x^3 - x}{x - 1} = x(x + 1) \][/tex]

Final Answer

Therefore, the overall expression simplifies to:

[tex]\[ \frac{f(x) - f(1)}{x - 1} = x(x + 1) \][/tex]