What is the value of (a + b)³ - a³ + b³ ?

Which one of the following pairs is not correctly matched?

The sum of the squares of two numbers is 545 and the square of their difference is 1. Find the product of the two numbers.

If $$x + y = 5$$ and xy = 4 , find the value of $$x^3 + y^3$$​.

The value of $$\left(x^{\frac{2}{3}} - x^{\frac{1}{3}}y^{\frac{1}{3}} + y^{\frac{2}{3}}\right)\left(x^{\frac{1}{3}} + y^{\frac{1}{3}}\right)$$​ is

(x + y + 2z)(x + y) can be expressed as

If $$x + \frac{1}{x} = 3$$, then $$x^2 + \frac{1}{x^2}$$ is:

If ​​​​​ $$a²- 4a +1= 0$$, find $$a² + \frac{1}{a^2}$$.​

Write the expanded form of $$(4a + 9b + 5c)^2.$$​​

Write the expanded form of $$(9a + 4b + 5c)^2$$​​

Find the square root of $$\frac{a^2}{b^2}+\frac{b^2}{a^2}+2$$ ​