find four numbers in ap whose sum is 28 and sum of whose square is 216
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hiii dear_________✌️✌️✌️✌️✌️
good evening________
Let the four numbers be (a-3d), (a-d), (a+d) & (a+3d).
Now According to question
Their sum :
(a-3d)+(a-d)+(a+d)+(a+3d)=28
4a = 28
a=7.
2.Their product
(a-3d)²+(a-d)²+(a+d)²+(a+3d)²=216
4a²+20d²=216
a² + 5d² = 54
Putting the value of a
49 + 5d² = 54
5d² = 5
d² = 1
d=±1.
Hence, the numbers are 4, 6, 8 & 10.
good evening________
Let the four numbers be (a-3d), (a-d), (a+d) & (a+3d).
Now According to question
Their sum :
(a-3d)+(a-d)+(a+d)+(a+3d)=28
4a = 28
a=7.
2.Their product
(a-3d)²+(a-d)²+(a+d)²+(a+3d)²=216
4a²+20d²=216
a² + 5d² = 54
Putting the value of a
49 + 5d² = 54
5d² = 5
d² = 1
d=±1.
Hence, the numbers are 4, 6, 8 & 10.
shimra44:
can u explain me the last step
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