Questions

What is The Formula of a Minus b Whole Cube?

A minus B Whole Cube

Are you looking for a minus b whole Cube? You can check the formulas of a minus b whole Cube in three ways. We are going to share the (a-b)^3 algebra formulas for you as well as how to create (A-B)^3 and proof.

we can write \( (a-b)^3 =  (a-b)^2 \times (a-b) \)

we know that what is the formulas of a minus b whole square. \(a-b)^2 = a^2 +b^2 – 2ab \) put the formulas.

\(=> (a-b)^3 = (a^2+b^2-2ab) \times (a-b)\)

\(=> (a-b)^3 = a \times (a^2+b^2-2ab) – b \times (a^2+b^2-2ab)\)

start multiplication

\(=> (a-b)^3 = a^3 + ab^2 – 2a^2 b – ba^2 – b^3 + 2ab^2 \)

Arrange

\(=> (a-b)^3 = a^3 + ab^2 + 2ab^2 – 2a^2 b – ba^2 – b^3 \)

\(=> (a-b)^3 = a^3 + 3 ab^2 – 3a^2 b – b^3 \)

Also Write : \(=> (a-b)^3 = a^3 – b^3 + 3 ab (b-a)  \)

(A-B)^3 Verifications

Need to verify \((a-b)^3\) formula is right or wrong. put the value of a = 5 and b=3

put the value of a and b in the LHS

\(=> (a-b)^3 = (5-3)^3 \)

\(=> (a-b)^3 = (2)^3 \)

\(=> (a-b)^3 = 8 \)

put the value of a and b in the RHS

\(=> a^3 + 3 ab^2 – 3a^2 b – b^3 \)

\(=> 5^3 + 3 \times 5\times 3^2 – 3\times 5^2\times 3 – 3^3 \)

put value of square and cube \(=> 125 + 3 \times 5\times 9 – 3\times 25\times 3 – 27 \)

start multiplication \(=> 125 + 15\times 9 – 75\times 3 – 27 \)

\(=> 125 + 135 – 225 – 27 \)

addition \(=> 260 – 252  \)

Simplify Calculation \(8\)

Therefore \( LHS = RHS \)

Proof Formulas \( (a-b)^3 = a^3 + 3 ab^2 – 3a^2 b – b^3 \)

 Summary (A+B)^3

If you have any issues in the (A-B)^3 formulas, please let me know through social media and mail. A minus B Whole Cube is the most important algebra maths formulas for class 6 to 13.