(27)
Answers
Solution:
27y³ + 125z³
☞ (3y)³ + (5z)³
☞ (3y + 5z)[(3y)² - 3y.5z + (5z)² ]
☞ (3y + 5z) [9y² - 15yz + 25z² ]
Identity Used for this Question:
a³ + b³ = ( a + b ) ( a² - ab + b² )
Important Identities :
☞ a³ + b³ = ( a + b ) ( a² - ab + b² )
☞ a³ - b³ = ( a - b ) ( a² + ab + b² )
QUESTIONS :-
ANSWER :-
Answer:
27x3−125y3=(3x−5y)(9x2+15xy+25y2)
Explanation:
Notice that both of the terms are perfect cubes:
27x3=(3x)3
125y3=(5y)3
So we can conveniently use the difference of cubes identity:
A3−B3=(A−B)(A2+AB+B2)
with A=3x and B=5y as follows:
27x3−125y3
=(3x)3−(5y)3
=(3x−5y)((3x)2+(3x)(5y)+(5y)2)
=(3x−5y)(9x2+15xy+25y2)
The remaining quadratic factor has no linear factors with Real coefficients. If we allow Complex coefficients then we can factor a little further:
=(3x−5y)(3x−5ωy)(3x−5ω2y)
where ω=−12+√32i is the primitive Complex cube root of 1.