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If the ath and bth term of an AP are 1/b...

If the ath and bth term of an AP are `1/b` and `1/a`,then show that (ab)th term is 1 and the sum upto first (ab) term Is `1/2(ab+1)`.

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If the xth term of an A.P. is (1)/(y) and its yth term is (1)/(x) then show that its xyth term is 1 and the sum of its first xy terms is (1)/(2)(xy+1) .

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UNITED BOOK HOUSE-MODEL QUESTION PAPERS-SET 11-EXERCISE
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  2. If (1+x)^n=c0+c1x+c2x^2+....+cnx^n,then show that c0/1+c2/3+c4/5+...=2...

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  3. If the ath and bth term of an AP are 1/b and 1/a,then show that (ab)th...

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  4. In /\XYZthe co-ordinate of Y and Z are (-a, 0) and (a, 0), andangle XZ...

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  5. If the three straight lines ax + 2y + 1 = 0, 3y + bx + 1 = 0 and cx+ 4...

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  6. If the circles x^2+y^2+2ax+c^2=0and x^2+y^2+2by+c^2=0touch each other,...

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  7. Find the co-ordinate of a point equidistance from the points' (0, 0. 0...

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  8. Prove that lim(xrarr1)(x^2-sqrtx)/(sqrtx-1)=3

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  9. Prove that sqrt5 is irrational, (use the method of contradiction).

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  10. In xy plane, |x — y | = 1 represents an equation of a circle and one d...

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  11. Find the mean diaviation with respect to median of the frequency dist...

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  12. If (acosthetasecphi-x)/(asin(theta+phi))=(y-bsinthetasecphi)/(bcos(th...

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  13. If sinalpha+sinbeta=1/2,cosalpha+cosbeta=5/4find the value of tanalpha...

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  14. Solve :(x+1)(x+2)(x+3)(x+4)=120

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  15. In a polygon, the mesurement of least internal angle is 120^@. If thea...

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  16. Out of 15 boys, 7 are skaut. In how mariy different way can 12 boys be...

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  17. Draw the graph of the following system of inequation and show the comm...

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  18. Find the equation of a parabola having the co-ordinate,of vertex is (-...

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  19. Find the equation of an ellipse having vertices (-1, 2)- and (9, 2) . ...

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  20. In each of the find the equations of the hyperbola satisfying the give...

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