Expanding (x+1)(x+3)
This expression represents the product of two binomials. To find the answer, we can use the FOIL method:
First: Multiply the first terms of each binomial:
- x * x = x²
Outer: Multiply the outer terms of the binomials:
- x * 3 = 3x
Inner: Multiply the inner terms of the binomials:
- 1 * x = x
Last: Multiply the last terms of each binomial:
- 1 * 3 = 3
Now, add all the terms together:
x² + 3x + x + 3
Finally, combine the like terms:
x² + 4x + 3
Therefore, the expanded form of (x+1)(x+3) is x² + 4x + 3.
Understanding the FOIL Method
The FOIL method is a mnemonic device that helps remember the steps involved in multiplying binomials. It stands for:
- First - multiply the first terms of each binomial
- Outer - multiply the outer terms of the binomials
- Inner - multiply the inner terms of the binomials
- Last - multiply the last terms of each binomial
By following these steps systematically, you can accurately expand any binomial multiplication.