Integration of Exponential, Logarithmic, and Hyperbolic Functions: Background You’ll Need 2

  • Make expressions simpler by applying the rules for multiplying, dividing, and raising numbers to powers

Simplifying Expressions Using the Rules for Multiplying, Dividing, and Raising Numbers to Powers

Simplifying expressions by applying the rules for multiplying, dividing, and raising numbers to powers is a fundamental skill in algebra and calculus. Mastery of this skill allows you to handle complex equations more efficiently and is crucial for understanding more advanced mathematical concepts, such as integrals, exponential functions, and logarithms.

The Power Rule for Exponents

Another word for an exponent is power. You have likely seen or heard an example such as [latex]3^5[/latex] can be described as [latex]3[/latex] raised to the [latex]5[/latex]th power. In this section, we will further expand our capabilities with exponents. We will learn what to do when a term with a power is raised to another power, what to do when two numbers or variables are multiplied and both are raised to an exponent, and what to do when numbers or variables that are divided are raised to a power. We will begin by raising powers to powers.

the power rule for exponents

For any positive number [latex]x[/latex] and integers [latex]a[/latex] and [latex]b[/latex]: [latex]\left(x^{a}\right)^{b}=x^{a\cdot{b}}[/latex].

Raise a Product to a Power

Raising a product to a power is a fundamental operation in algebra that demonstrates how exponents interact with multiplication. This operation is widely used across various mathematical disciplines, including geometry, where it might be used to calculate the volume of shapes, and in finance, where it can be used to calculate compounded interest over multiple periods.

The rule simplifies the process of working with powers of products. Instead of multiplying the base numbers repeatedly, we apply the exponent to each factor individually. This is based on the distributive property of exponents over multiplication.

a product raised to a power

For any nonzero numbers [latex]a[/latex] and [latex]b[/latex] and any integer [latex]x[/latex], [latex]\left(ab\right)^{x}=a^{x}\cdot{b^{x}}[/latex].

Simplify the following: 

[latex]\left(2yz\right)^{6}[/latex]

If the variable has an exponent with it, use the Power Rule: multiply the exponents.

Simplify the following:

[latex]\left(−7a^{4}b\right)^{2}[/latex]

The Product Rule for Exponents

The Product Rule for Exponents is one of the essential rules in algebra that simplifies the process of working with powers. This rule is pivotal when dealing with exponential expressions, particularly when multiplying them. In essence, it tells us that when we multiply two exponents with the same base, we can simply add the exponents to get the new power of the base.

This rule is extremely useful in various mathematical and real-world applications, such as calculating compound interest, understanding scientific notation, or solving problems in physics and engineering. By using the Product Rule, we can manage and simplify complex expressions without the need for lengthy multiplication.

the product rule for exponents

For any number [latex]x[/latex] and any integers [latex]a[/latex] and [latex]b[/latex], [latex]\left(x^{a}\right)\left(x^{b}\right) = x^{a+b}[/latex].
 
To multiply exponential terms with the same base, add the exponents.

CautionCaution! When you are reading mathematical rules, it is important to pay attention to the conditions on the rule. For example, when using the product rule, you may only apply it when the terms being multiplied have the same base and the exponents are integers. Conditions on mathematical rules are often given before the rule is stated, as in this example it says “For any number [latex]x[/latex] and any integers [latex]a[/latex] and [latex]b[/latex].”

Simplify the following:

[latex](a^{3})(a^{7})[/latex]

When multiplying more complicated terms, multiply the coefficients and then multiply the variables.

Simplify the following:

[latex]5a^{4}\cdot7a^{6}[/latex]

The Quotient (Division) Rule for Exponents

The Quotient Rule for Exponents is as crucial as the Product Rule and serves as its counterpart for division. This rule assists in simplifying expressions where we have exponential terms with the same base being divided. It states that when you divide exponents with the same base, you can subtract the exponents.

This rule has significant practical applications, especially in fields that involve calculations of rates of change, decay, or growth when they are decreasing, such as in the case of depreciation in finance or radioactive decay in physics.

the quotient (division) rule for exponents

For any non-zero number [latex]x[/latex] and any integers [latex]a[/latex] and [latex]b[/latex]:

[latex]\displaystyle \frac{{{x}^{a}}}{{{x}^{b}}}={{x}^{a-b}}[/latex]

To divide exponential terms with the same base, subtract the exponents.

Evaluate the following:

[latex]\displaystyle \frac{{{4}^{9}}}{{{4}^{4}}}[/latex]

When dividing terms that also contain coefficients, divide the coefficients and then divide variable powers with the same base by subtracting the exponents.

Simplify the following:

[latex]\displaystyle \frac{12{{x}^{4}}}{2x}[/latex]