Two APs have the same common difference. The first term of one of these is -1 and that of the other is -8. Then the difference between their 4th terms is a) -1 b) -8 c) 7 d) 9
Answers
Answered by
31
GIVEN :–
• Two A.P.'s have the same common difference.
• The first term of one of these is -1 and that of the other is -8.
TO FIND :–
• Difference between their 4th terms is = ?
SOLUTION :–
• We know that –
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• For first A.P. ( 4th term ) –
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• So that –
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• For second A.P.( 4th term ) –
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• So that –
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• Now difference –
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▪︎Hence, Option (c) is correct.
Answered by
26
Answer:
c) 7
Step-by-step explanation:
a4 = a'4
an = a + (n - 1)d
a + (4 - 1)d = a' + (4 - 1)d
a + 3d = a' + 3d
Given that, the first term of one of these is -1 and that of the other is -8.
→ a4 - a'4
→ -1 + 3d - [(-8) + 3d]
→ -1 + 3d + 8 - 3d
→ 7
Hence, the difference between their 4th terms is 7.
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