3.) A *the first one*
4.) C *the last one*
F^-1= positive or negative x square root
40x - 2 because you combine like terms so it's 40x and then combine 8 and -10
Solution:
The difference of cubes identity is
if a and b are any two real numbers, then difference of their cubes , when taken individually:
→a³ - b³= (a-b)(a² + a b + b²)→→→Option (D) is true option.
I will show you , how this identity is valid.
Taking R H S
(a-b)(a² +b²+ab)
= a (a² +b²+ab)-b(a² +b²+ab)
= a³ + a b² +a²b -b a² -b³ -ab²
Cancelling like terms , we get
= a³ - b³
= L H S
