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In an examination 20question of true-fal...

In an examination 20question of true-false are asked. Suppose a student tosses a fair coin to determine his answer to each question. If the coin falls heads, the answer 'true', if it falls tails, he answers. 'false' find the probabilities that he answers at least 12 questions correctly

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The correct Answer is:
`1/2^(20)[.^(20)C_(12)+.^(20)C_(13)+......+.^(20)C_(20)]`
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SUNSTAR PUBLICATION-P.U .BOARD LATEST MODEL QUESTION PAPER - 2 -PART-C
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  2. Find the absolute maximum value and the absolute minimum value of the ...

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  3. Find int(xe^(x))/((1+x)^(2))dx

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  4. Evaluate: int2/((1-x)(1+x^(2)))dx

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  5. Find the area bounded by the the curve y=cos x between x=0 and x=2pi.

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  6. Find the general solution of dy/dx+y=1(y!=1)

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  7. Find the value of p so that the lines (1-x)/3=(7y-14)/(2p)=(z-3)/2 and...

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  8. Find the area of the rectangle having vertices A,B,C and D with positi...

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  9. Show that four points A,B,C and D with position vectors4i+5j+k,-(j+k),...

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  10. In answering a question on a multiple choice test a student either kno...

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  11. If f:ArarrA defined by f(x)=(4x+3)/(6x-4) where A=R-{2/3}, show that f...

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  12. If A=((1,1,-1),(2,0,3),(3,-1,2)),B=[(1,3),(0,2),(-1,4)] and C=[(1,2,3,...

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  13. Solve by matrix method: 4x+3y+2z=60, x+2y+3z=45, 6x+2y+3z=70

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  14. If y=3 cos(log x)+4sin(logx) show that x^(2)y(2)+xy(1)+y=0

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  15. A ladder 5cm long is leaning against a wall. The bottom of the ladder ...

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  16. Find the integral of sqrt(x^(2)-a^(2) with respect to x.

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  17. Find the area of the smaller region enclosed by the circle x^(2)+y^(2)...

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  18. Solve the differential equation dy/dx+2y tan x=sin x,y=0 when x=pi/3

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  19. Derive the equation of a plane perpendicular to a given vector and pas...

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  20. In an examination 20question of true-false are asked. Suppose a studen...

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