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In an A.P. the pth and qth terms are res...

In an A.P. the pth and qth terms are respectively a and b. Show that the sum of first p + q terms is `(p+q)/2{(a+b)+(a-b)/(p-q)}`.

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KALYANI PUBLICATION-PROGRESSION-EXERCISE
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  3. In an A.P. the pth and qth terms are respectively a and b. Show that t...

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  4. If the first terms, second term and the last term of an A.P. are respe...

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  6. The first term of an A.P. is a. If sum of first p terms is zero, pro...

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  8. Find the sum of all odd numbers lying between 12 and 90.

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  9. Determine the sum of the numbers lying between 100 and 500 which are d...

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  10. Find the sum of all numbers lying between 1 and 100 which are divisibl...

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  11. Determine the sum of the numbers lying between 100 and 200 which are n...

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  12. Determine the sum of following series upto n terms. 1.2+2.3+3.4+…….

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  13. Determine the sum of following series upto n terms. 1.1+2.3+3.5+…….

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  14. Determine the sum of following series upto n terms. 2.1+3.3+4.5+…….

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  15. Determine the sum of following series upto n terms. 3.8+6.11+9.14+……...

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  16. Determine the sum of following series upto n terms. 1.3+2.4+3.5+…….

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  17. Determine the sum of following series upto n terms. 1.3+5.7+9.11+…….

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  18. Determine the sum of following series upto n terms. (3^2-2^2)+(5^2-4...

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  19. Determine the sum of following series upto n terms. (1^2-2^2)+(3^2-4...

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  20. Determine the sum of following series upto n terms. 1.2^2+2.3^2+3.4^...

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