Resolve x^18- y^18 into five factors.
Answers
Answer:
Please see the attachment
Answer:
( x + y ) ( x - y ) ( x² + y² - xy ) ( x² + y² + xy ) ( x⁶ + y⁶ - x³y³ ) ( x⁶ + y⁶ + x³y³ )
Step-by-step explanation:
Given----> x¹⁸ - y¹⁸
To find ----> Factors of given expression
Solution-----> We know that,
1) a² - b² = ( a + b ) ( a - b )
2) a³ + b³ = ( a + b ) ( a² + b² - ab )
3) a³ - b³ = ( a - b ) ( a² + b² + ab )
Now,
x¹⁸ - y¹⁸ = ( x⁹ )² - ( y⁹ )²
Applying first identity , we get ,
= ( x⁹ + y⁹ ) ( x⁹ - y⁹ )
= { ( x³)³+( y³ )³ } { ( x³ )³ - ( y³ )³ }
Applying second and third identity , we get ,
= ( x³ + y³ ) { ( x³)² + ( y³ )² - x³y³ } ( x³ - y³ ) { ( x³ )² +
( y³ )² + x³ y³ }
Applying second and third identity again , we get
= ( x + y ) ( x² + y² - xy ) ( x⁶ + y⁶ - x³ y³ ) ( x - y ) ( x² + y² + xy ) ( x⁶ + y⁶ + x³y³ )
= ( x + y ) ( x - y ) ( x² + y² - xy ) ( x² + y² - xy ) ( x⁶ + y⁶ - x³y³ ) ( x⁶ + y⁶ + x⁶ y⁶ )