Which of the following statement is a tautology?

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Which of the following statement is a tautology?
Let
Then is continuous on the set
If and are sides of two squares such that , then the rate of change of area of the second square with respect to that of the first square is
The acute angle between the line and the line which makes equal intercepts with the co-ordinate axes is
The function is increasing in the set
If are statements, where, are matrices,
q:
r:
s: Maximum value of is 70 then the statement from the following having truth value true is โฆ.
The minimum value of where is
If is a matrix of order 2 and is the identity matrix of order 2 such that then
A-3I
In a triangle with usual notations if , then the value of
In a triangle PQR with usual notations, . If and are the roots of the equation , then
If , then the value of is
Considering only the principal values of the inverse trigonometric functions, the value of is
If the area bounded by the curve -axis and the line is divided into equal areas by the line , then the value of is โฆ
32
If , then
28
The equation of the curve passing through the point given that the sum of the ordinate and abscissa of any point exceeds the slope of the tangent to the curve at that point by 5 is
Let z be the complex number such that where , then
The solution of the differential equation is
, where c is the constant of integration
, where c is the constant of integration
, where c is the constant of integration
, where c is the constant of integration
, where c is the constant of integration.
, where c is the constant of integration.
, where c is the constant of integration.
, , where c is the constant of integration.
If the angles and C of a triangle are in A.P. and if and c denote the length of the sides opposite to and C respectively, then the value of is
If the pair of lines and have one line common, then
The number of ways in which 6 boys and 4 girls can be seated around a round table such that 2 special boys and a special girl never sit together is
332620
332540
332640
332520
The differential equation representing the family of parabolas having vertex at the origin and axis along the positive Y -axis is
(where k is the integration constant) then values of and D are respectively,
The probability that a non leap year selected at random will contain 52 Saturdays or 53 Sundays is
The population of towns A and B increase at the rate proportional to their population present at that time. At the end of the year 1984, the population of both the towns was 20,000 . At the end of the year 1989, the population of town A was 25,000 and that of town B was 28,000 . The difference of populations of towns A and B at the end of 1994 was
5950
8000
7950
6950
The vectors and are such that . If the projection of on is equal to projection of on and is perpendicular to , then the value of is
Two tangents to the circle at the points A and B meet at . Then the area of quadrilateral PAOB, where ' ' is the origin is
sq. units
sq. units
sq. units
sq. units
The lines and are
intersecting at point
intersecting at right angles
do not intersect
intersecting at point
, where c is the constant of integration
, where c is the constant of integration
, where c is the constant of integration
, where is the constant of integration
A random variable has the following probability distribution :
The mean and standard deviation of are respectively
The values of for which the angle between the vectors and is obtuse, are
If are three coplanar vectors such that and the angle between and is then the value of is
If and then .
u
v
The line intersects the XY plane and the YZ plane at points A and B respectively. The equation of line through the points A and B is
A fair faced die is rolled repeatedly until a number less than appears. If the mean of the number of tosses required is , then where
4
6
8
10
A fair coin is tossed a fixed number of times. If the probability of getting 5 tails is same as the probability of getting 7 tails, then the probability of getting 3 tails is

In the above figure, P divides AC in the ratio and Q divides BC in the ratio . Then M divides AQ in the ratio
The tangent to the ellipse making equal intercepts on the co-ordinate axes intersects the X -axis and the Y -axis in the points and respectively. Then (where O is origin)
sq. units
25 sq. units
sq. units
sq. units
The distance of the point from the plane measured along the line is
The direction cosines of a normal to the plane passing through and are โฆ..
The unit vectors perpendicular to the plane determined by the points , is
The equation of the plane passing through the point and through the line of intersection of and is
A manufacturing company produces two items, A and B. Each toy should be processed by two machines, I and II. Machine I can be operated for maximum 10 hours 40 minutes. It takes 20 minutes for an item of A and 15 minutes for B. Machine II can be operated for a total time at 8 hours 20 minutes. It takes 5 minutes for an item A and 8 minutes for B . The profit per item of is and per item of is โน 18 . The formulation of an L.P.P. to maximize the profit (where is number of items A and is the number of item ) is
Maximize
then the value of is
If and Then takes the value
If , then .
The equation of the tangent to the curve at the point where it crosses the Y axis is