There is certain number of rows of chairs in a room .The number of chairs in each row is thrice the total number of rows. Find the number of charis in each row and number of rows in the room if the total number of chairs is 2187
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Let for `A=[(1,0,0),(2,1,0),(3,2,1)]`, there be three row matrices `R_(1), R_(2)` and `R_(3)`, satifying the relations, `R_(1)A=[(1,0,0)], R_(2)A=[(2,
Correct Answer - D `overset(B)([(-,R_(1),-),(-,R_(2),-),(-,R_(3),-)])overset(A)([(1,0,0),(2,1,0),(3,2,1)])=overset(C)([(1,0,0),(2,3,0),(2,3,1)])` (1) `:.` (det. B) (det. A)=3 `:.` (det. B)=3 [as det. A=1] det. `(2A^(100)B^(3)-A^(99)B^(4))` = det. `(A^(99) (2A-B)B^(3))` `=("det. A")^(99)xxdet. (2A-B)xx("det B")^(3)` Now from (1), we...
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Find the locus of the point from which the two tangents drawn to the parabola `y^2=4a x` are such that the slope of one is thrice that of the other.
Correct Answer - `3y^(2)=16ax` Let the point be (h,k). Let any tangent be `y=mx+(a)/(m)` `or" "k=mh+(a)/(m)orm^(2)h-mk+a=0` Its roots are `m^(1)and3m_(1)`. Therefore, `m_(1)+3m_(1)=(k)/(h)` `m_(1)*3m_(1)=(a)/(h)` Eliminating `m^(1)`, we get the locus as `3y^(2)=16ax`
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One dimensional array may have…….. A. Only columns B. Only rows C. Only one cell D. Both columns and rows
Correct option is: D. Both columns and rows
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A concave mirror forms a real image, on a screen of thrice the linear dimension of a real object placed on its principal axis. The mirror is moved by
Correct Answer - `60 cm`
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There is a certain sequence of positive real numbers. Beginning from the third term, each term of the sequence is the sum of all the previous terms. T
Correct Answer - B `(b)` Sequence is `t_(1)+t_(2)+t_(3)+t_(4)+…` `t_(3)=t_(1)+t_(2)`, `t_(7)=1000` `t_(1)=1` but `t_(7)=t_(1)+t_(2)+t_(3)+t_(4)+t_(5)+t_(6)` `1000=2(t_(1)+t_(2)+t_(3)+t_(4)+t_(5))` `=4(t_(1)+t_(2)+t_(3)+t_(4))` `=8(t_(1)+t_(2)+t_(3))` `=16(t_(1)+t_(2))` `:.t_(1)+t_(2)=125//2` `:. t_(2)=125//2-1=123//2`
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There are two rows of capacitos in series, the capacitance of ecah capacitor bein C. The rows are branched by a number of cpacitors of the same capaci
Correct Answer - `1/2(sqrt3-1)C`
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A room contains air in which the speed of sound is `340m//s.` The walls of the room are made of concrete in which the speed of sound is `1700m//s` (a)
Correct Answer - (a) `sin^(-1) ((1)/(5))`; (b) air
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“There’s been a row”- the row took place because –
A man was trying to hunt rabbits and the keepers could hear the noise of it. The man thought they did not see him because of the darkness, the man...
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A ball is thrown from a comer of room of length 20 m and height 5 m such that the ball moves along the length of room just touching the ceiling and dr
Correct Answer - (i)`45^(@)` (ii)`10sqrt(2)m//s` (iii) 2 sec
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A student sitting in the last row of the class room is not able to read clearly the writing on the black board
Correct option is A) myopia
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