find three number in an ap .whose sum and product are 21 and 343 respectively.
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Step-by-step explanation:
a+a+d+a+2d = 21
3a+3d = 21
a+d = 7
A(2) = 7
a(a+d)(a+2d) = 343
7a(a+2d) = 343
7a{a+2(7-a)} = 343
7a{a+14-2a} = 343
a{14-a} = 49
14a-a² = 49
a²-14a+49 = 0
(a-7)² = 0
a = 7 , 7
d = 7-7 = 0
These terms are 7 , 7 & 7
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