Question

Use a horizontal format to add or subtract. $$\left(x^{3}+x^{2}+1\right)-x^{2}$$

Short answer

The simplified result of \(x^{3}+x^{2}+1 - x^{2}\) is \(x^{3}+1\).

Step-by-step solution

Align Like Terms

First, align the like terms in both polynomial expressions, which are terms that have the same variable and exponent. We can represent the problem as \(x^{3}+x^{2}+1 - (x^{2})\).

Subtract Like Terms

Then, subtract the like terms individually. For the \(x^{2}\) terms, \(x^{2} - x^{2} = 0x^{2}\) or simply 0. None of the other terms in the first polynomial have matches in the second polynomial, so they remain unchanged.

Write the Final Solution

Write the final polynomial, containing all the subtracted and unchanged terms. Any terms that resulted in zero can be removed.

Key concepts

Align Like Terms

When dealing with polynomial subtraction, one of the first steps is to align like terms. Like terms are terms that have exactly the same variable parts, which means they have the same base and exponent. For example, in \(x^{3}+x^{2}+1 - x^{2}\), the like terms are the ones with \(x^{2}\).
By aligning like terms, you're setting up the equation so that each term in the first polynomial is above or below its corresponding term in the second polynomial (if there is one). This is similar to stacking numbers for traditional subtraction, where you place tens above tens and ones above ones. The concept is crucial because it allows for clear and organized subtraction of terms, which decreases the chance of making errors during calculation.

Subtract Like Terms

Once your terms are aligned, the next step is to subtract like terms. This process is straightforward; you take the coefficient (the numerical part) of a term in the first polynomial and subtract from it the coefficient of the matching term in the second polynomial. Following our example, we have \(x^{3}+x^{2}+1-(x^{2})\), which means we subtract the \(x^{2}\) terms from each other. This subtraction results in \(x^{2}-x^{2}=0\).
It's important to remember that when terms cancel each other out, they effectively become zero. However, there's no need to write '0' terms in a polynomial, as they don't affect the value. After you've subtracted the like terms, the next and final step is simplification.

Simplify Polynomials

The ultimate goal of polynomial subtraction is to simplify the polynomial as much as possible. To do this, you must remove any terms that cancel out, such as any '0' terms that result from the subtraction of like terms. After subtraction, you will write down all the terms that are left. In our case, the \(x^{2}\) terms canceled out, so we are left with \(x^{3}+1\).
Simplifying a polynomial can also include combining any like terms that might still be present after subtraction, although this doesn't apply to our example. By simplifying the polynomial, you make it more concise and easier to work with for any further operations or when graphing the polynomial function. Always ensure that your final simplified polynomial is written in descending order of degree, with the term having the highest exponent first, then the next lower one, and so on.