If a+b =11 and a²+b²=65 then what is the value of a³+b³?!????!
devita , 8 Years ago
Grade 9
9 grade maths> If a+b =11 and a²+b²=65 then what is the ...
2 AnswersManish
If a+b = 11 and,a²+b²=65 so ,(a+b)² = a²+b²+2ab , Put 11 in a+b and 65 in a²+b² to get ab(11)²= 65 + 2ab121 = 65 + 2ab2ab = 56ab = 28Put the value of ab in :a³+b³ = (a+b)³ - 3ab( a+b) = (11)³ - 3×28(11) = 1331 - 924 = 407
Soumendu Majumdar
Dear Student,
Put (a+b) = 11 & 
= 65
so
implies 2 ab = 56
so ab =28
Now,
Hope it helps!
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