Question

expand using formula [28]cube

Answer 1

Answer:

Step-by-step explanation:

Expanding using formula of (x+y)  

3

 

                  (x+y)  

3

=x  

3

+3x  

2

y+3xy  

2

+y  

3

     

                  Replacing x = 3a and y = 4b

                   

3

=(3a+4b)  

3

 

                  (3a+4b)  

3

=(3a)  

3

+3(3a)  

2

(4b)+3(3a)(4b)  

2

+(4b)  

3

                    [Using eqn (1)]

                  (3a+4b)  

3

=27a  

3

+108a  

2

b+144ab  

2

+64b  

3

 

Hence, (3a+4b)  

3

=27a  

3

+108a  

2

b+144ab  

2

+64b  

3