Question
The sum of two numbers is 18 while the sum of their
squares is 164. Find the sum of the cubes of those two numbers.Solution
Let the number is a and b. ATQ- a+b =18 a2+b2 =164 (a+b)2 = a2+b2 +2ab. 18×18 =164+2ab 2ab =324-164=160. ab =80 (10,8) is the co prime factor of 80. So, a=10, and b =8 Now, a3+b3=1000+512=1512.
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