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If in a triangle DeltaABC,a^(2)cos^(2)A-...

If in a triangle `DeltaABC,a^(2)cos^(2)A-b^(2)-c^(2)=0`, then

A

`(pi)/(4)ltAlt(pi)/(2)`

B

`(pi)/(2)ltAltpi`

C

`A=(pi)/(2)`

D

`Alt(pi)/(4)`

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WB JEE PREVIOUS YEAR PAPER-QUESTION PAPER 2015-MULTIPLE CHOICE QUESTIONS
  1. If the letters of the word PROBABILITY are written down at random in a...

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  2. The least value of t so that the lines x=t+alpha,y+16=0 and y=ax are c...

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  3. If in a triangle DeltaABC,a^(2)cos^(2)A-b^(2)-c^(2)=0, then

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  4. {x""inR":"|cosx|gesinx}cap[0,(3pi)/(2)]

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  5. The number of distinct real roots of |(sinx,cosx,cosx),(cosx,sinx,co...

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  6. Let x(1),x(2),.........x(15) be 15 distinct numbers chosen from 1,2,3,...

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  7. Let [x] denote the greatest integer less than or equal to x Then the v...

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  8. A particle starts moving from rest from a fixed point in a fixed direc...

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  9. lim(nto oo)(sqrt1+sqrt2+......+sqrt(n-1))/(nsqrtn)=

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  10. If lim(xto0)(axe^(x)-blog(1+x))/(x^(2))=3 then the values of a, b are ...

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  11. Area of the region bonuded by y=|x|andy=-|x|+2 is

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  12. Let d(n) denote the number of divisors of n inciuding 1 and iteslf . T...

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  13. The trigonometric equation sin^(-1)x=2sin^(-1)2a has a real solution i...

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  14. If 2+i and sqrt5-2i are the roots of the equation (x^(2)+ax+b)(x^(2)+c...

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  15. Let P(x) be a polynomial, which when divided by x-3 and x-5 leaves rem...

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  16. The integrating factor of the differential equation (dy)/(dx)+(3x^(2)t...

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  17. If y=e^(-x)cos2x then which of the following differential equations is...

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  18. Let f(x) denote the fractional part of a real numbers x. Then the valu...

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  19. Let S={(a,b,c)inNxxNxxN:a+b+c=21,aleblec} and T={(a,b,c)inNxxNxxN:a,b,...

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  20. Let y=e^(x^(2)) and y=e^(x^(2))sinx be two given curves. Then the angl...

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