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Square of a Binomial Calculator.

Expand (a + b)² using the binomial identity.

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Result

result: 25.00000000

Use Cases

Algebra Homework Help

Quickly verify your manual expansion of squared binomials, ensuring accuracy in your algebra assignments.

Example: Check that (x + 3)^2 expands to x^2 + 6x + 9.

Simplifying Expressions

Use the calculator to simplify expressions that involve squaring a binomial, saving time in more complex calculations.

Example: Simplify (2a - 5)^2 to 4a^2 - 20a + 25.

Frequently Asked Questions

What does the Square of a Binomial Calculator do?: It expands a binomial squared, such as (a + b)^2 or (a - b)^2, into its polynomial form. You enter the values for a and b, and the calculator shows the expanded expression.
How do I use the calculator?: Simply enter the values for a and b in the input fields. The calculator will compute the square of the binomial and display the expanded form, following the formula (a ± b)^2 = a^2 ± 2ab + b^2.
Can I use this calculator for negative numbers?: Yes, you can enter negative values for a and b. The calculator will handle the signs correctly and produce the expanded form, which may include negative coefficients.

Tips & Common Mistakes

Tips

Remember the formula: (a + b)^2 = a^2 + 2ab + b^2, and (a - b)^2 = a^2 - 2ab + b^2.
Double-check your input values for a and b to avoid errors in the expansion.
Use the calculator to practice and confirm your understanding of binomial expansion.
If you have a binomial like (2x + 3)^2, enter a = 2x and b = 3, but note that the calculator expects numeric values, so you may need to substitute variables with numbers.

Common Mistakes to Avoid

Forgetting the middle term: many users incorrectly write (a + b)^2 as a^2 + b^2, omitting the 2ab term.
Misapplying signs: when expanding (a - b)^2, some forget the negative sign in the middle term, writing a^2 + 2ab + b^2 instead of a^2 - 2ab + b^2.
Entering variables instead of numbers: the calculator expects numeric values for a and b, so entering algebraic expressions like 'x' will not work.

Last updated: August 13, 2026

Use Cases

Algebra Homework Help

Quickly verify your manual expansion of squared binomials, ensuring accuracy in your algebra assignments.

Example: Check that (x + 3)^2 expands to x^2 + 6x + 9.

Simplifying Expressions

Use the calculator to simplify expressions that involve squaring a binomial, saving time in more complex calculations.

Example: Simplify (2a - 5)^2 to 4a^2 - 20a + 25.

Frequently Asked Questions

What does the Square of a Binomial Calculator do?

It expands a binomial squared, such as (a + b)^2 or (a - b)^2, into its polynomial form. You enter the values for a and b, and the calculator shows the expanded expression.

How do I use the calculator?

Simply enter the values for a and b in the input fields. The calculator will compute the square of the binomial and display the expanded form, following the formula (a ± b)^2 = a^2 ± 2ab + b^2.

Can I use this calculator for negative numbers?

Yes, you can enter negative values for a and b. The calculator will handle the signs correctly and produce the expanded form, which may include negative coefficients.

Tips & Common Mistakes

Tips

Remember the formula: (a + b)^2 = a^2 + 2ab + b^2, and (a - b)^2 = a^2 - 2ab + b^2.
Double-check your input values for a and b to avoid errors in the expansion.
Use the calculator to practice and confirm your understanding of binomial expansion.
If you have a binomial like (2x + 3)^2, enter a = 2x and b = 3, but note that the calculator expects numeric values, so you may need to substitute variables with numbers.

Common Mistakes to Avoid

Forgetting the middle term: many users incorrectly write (a + b)^2 as a^2 + b^2, omitting the 2ab term.
Misapplying signs: when expanding (a - b)^2, some forget the negative sign in the middle term, writing a^2 + 2ab + b^2 instead of a^2 - 2ab + b^2.
Entering variables instead of numbers: the calculator expects numeric values for a and b, so entering algebraic expressions like 'x' will not work.

Use Cases

Algebra Homework Help

Quickly verify your manual expansion of squared binomials, ensuring accuracy in your algebra assignments.

Example: Check that (x + 3)^2 expands to x^2 + 6x + 9.

Simplifying Expressions

Use the calculator to simplify expressions that involve squaring a binomial, saving time in more complex calculations.

Example: Simplify (2a - 5)^2 to 4a^2 - 20a + 25.

Frequently Asked Questions

What does the Square of a Binomial Calculator do?

It expands a binomial squared, such as (a + b)^2 or (a - b)^2, into its polynomial form. You enter the values for a and b, and the calculator shows the expanded expression.

How do I use the calculator?

Simply enter the values for a and b in the input fields. The calculator will compute the square of the binomial and display the expanded form, following the formula (a ± b)^2 = a^2 ± 2ab + b^2.

Can I use this calculator for negative numbers?

Yes, you can enter negative values for a and b. The calculator will handle the signs correctly and produce the expanded form, which may include negative coefficients.

Tips & Common Mistakes

Tips

Remember the formula: (a + b)^2 = a^2 + 2ab + b^2, and (a - b)^2 = a^2 - 2ab + b^2.
Double-check your input values for a and b to avoid errors in the expansion.
Use the calculator to practice and confirm your understanding of binomial expansion.
If you have a binomial like (2x + 3)^2, enter a = 2x and b = 3, but note that the calculator expects numeric values, so you may need to substitute variables with numbers.

Common Mistakes to Avoid

Forgetting the middle term: many users incorrectly write (a + b)^2 as a^2 + b^2, omitting the 2ab term.
Misapplying signs: when expanding (a - b)^2, some forget the negative sign in the middle term, writing a^2 + 2ab + b^2 instead of a^2 - 2ab + b^2.
Entering variables instead of numbers: the calculator expects numeric values for a and b, so entering algebraic expressions like 'x' will not work.