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If 1+2 + 3+…..n terms = 28 , then n is e...

If 1+2 + 3+…..n terms = 28 , then n is equal to

A

28

B

7

C

8

D

56

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CPC CAMBRIDGE PUBLICATION-PRACTICE QUESTION PAPER 12-ANSWER THE FOLLOWING QUESTION
  1. If 1+2 + 3+…..n terms = 28 , then n is equal to

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  2. If the product of zeroes of polynomial f(y) =ay^3 - 6y^2 + 11y -6 is 4...

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  3. What is the value of C, if ax^2 + bx +c =0 has equal roots ?

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  4. Find the second term if sum of the 'n' tem of an AP is 2n^2 +1 .

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  5. State converse of Pythagoras Theorem.

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  6. What is the p/q (p,q in z , q ne 0) form of 0.5bar(7) ?

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  7. If sin theta =1/3 , then find the value of (2cot^2 theta +2)

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  8. In sin (A+B) =(sqrt(3))/(2) and cos (A-B)=1, 0 lt A +B lt 90^@ , A ge ...

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  9. The surface area of a sphere is same as the C.S.A of a right circular ...

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  10. Prove that if x and y are odd positive integers , then x^2 +y^2 is eve...

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  11. Solve : 100x + 200 y =700 200x+100 y=800

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  12. Find the roots of the quadratic equation 3x^2 -2sqrt6 x + 2 =0 by for...

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  13. Find the value of x in which the points (1,-1) (x,1) and (4,5) are col...

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  14. ABC is a right angle triangle having angleB=90^@ . If BD=DC, show tha...

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  15. Prove that ara of the equilateral triangle described on the sides of s...

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  16. A box contains 90 dices which are numbered from 1 to 90. If one dise i...

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  17. Draw a pair of tangents to a circle of radius 5 cm which are inclined ...

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  18. Prove that (tan theta + sin theta)/(tan theta - sin theta) =(sec theta...

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  19. Asha is 5 times as old as her daughter Usha, 5 years later Asha will b...

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  20. The sum of 2 digits of a 2 digits number is 12 the number obtained by ...

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  21. Find the other two zeroes of the polynomial y^(4)+y^(3)-9y^(2)-3y+18 i...

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