question_answer14) If one root of the equation\[{{x}^{2}}+px+12=0\]is 4, while the equation\[{{x}^{2}}+px+q=0\]has equal roots, then the value of 'q' is
question_answer15) The coefficient of the middle term in the binomial expansion in powers of\[x\]of\[{{(1+\alpha x)}^{4}}\] and of\[{{(1-ax)}^{6}}\]is the same, if a equals
question_answer17) If\[{{S}_{n}}=\sum\limits_{r=0}^{n}{\frac{1}{^{n}{{C}_{r}}}}\]and\[{{t}_{n}}=\sum\limits_{r=0}^{n}{\frac{r}{^{n}{{C}_{r}}}}\]then\[\frac{{{t}_{n}}}{{{S}_{n}}}\]is equal to
question_answer18) Let\[{{T}_{r}}\]be the rth term of an AP whose first term is a and common difference is d. If for some positive integers \[m,n,m\ne n,{{T}_{m}}=\frac{1}{n}\]and\[{{T}_{n}}=\frac{1}{m},\]then\[a-d\]equals
question_answer19) The sum of the first\[n\]terms of the series \[{{1}^{2}}+{{2.2}^{2}}+{{3}^{2}}+{{2.4}^{2}}+{{5}^{2}}+{{2.6}^{2}}+....\]is \[\frac{n{{(n+1)}^{2}}}{2},\] when n is even. When n is odd, the sum is
question_answer22) If\[u=\sqrt{{{a}^{2}}{{\cos }^{2}}\theta +{{b}^{2}}{{\sin }^{2}}\theta }\] \[+\sqrt{{{a}^{2}}{{\sin }^{2}}\theta +{{b}^{2}}{{\cos }^{2}}\theta },\] then the difference between the maximum and minimum values of\[{{u}^{2}}\]is given by
question_answer23) The sides of a triangle are\[\sin \alpha ,\text{ }\cos \alpha \]and\[\sqrt{1+\sin \alpha \cos \alpha }\]for some\[0<\alpha <\frac{\pi }{2}\]. Then, the greatest angle of the triangle is
question_answer24) A person standing on the bank of a river observes that the angle of elevation of the top of a tree on the opposite bank of the river is \[60{}^\circ \]and when he retires 40 m away from the tree, the angle of elevation becomes\[30{}^\circ \]. The breadth of the river is
question_answer28) If\[\underset{x\to \infty }{\mathop{\lim }}\,{{\left( 1+\frac{a}{x}+\frac{b}{{{x}^{2}}} \right)}^{2x}}={{e}^{2}},\]then the values of a and b are
question_answer32) A function\[y=f(x)\]has a second order derivative\[f'\,'=6(x-1)\]. If its graph passes through the point (2, 1) and at that point, the tangent to the graph is\[y=3x-5,\]then the function is
question_answer41) If\[f(x)=\frac{{{e}^{x}}}{1+{{e}^{x}}},{{I}_{1}}=\int_{f(-a)}^{f(a)}{x}g\{x(1-x)\}dx\]and\[{{I}_{2}}=\int_{f(-a)}^{f(a)}{g\{x(1-x)\}dx},\] then the value of\[\frac{{{I}_{2}}}{{{I}_{1}}}\]is
question_answer45) Let A (2, - 3) and B (- 2,1) be vertices of a\[\Delta ABC\] If the centroid of this triangle moves on the line \[2x+3y=1,\]then the locus of the vertex C is the line
question_answer49) If a circle passes through the point [a, b) and cuts the circle\[{{x}^{2}}+{{y}^{2}}=4\]orthogonally, then the locus of its centre is
question_answer50) A variable circle passes through the fixed point \[A(p,\text{ }q)\]and touches x-axis. The locus of the other end of the diameter through A is
question_answer51) If the lines\[2x+3y+1=0\]and\[3x-y-4=0\]lie along diameters of a circle of circumference\[10\pi ,\]then the equation of the circle is
question_answer53) If\[a\ne 0\]and the line\[2bx+3cy+4d=0\]passes through the points of intersection of the parabolas\[{{y}^{2}}=4\text{ }ax\]and\[{{x}^{2}}=4\text{ }ay,\]then
question_answer54) The eccentricity of an ellipse with its centre at the origin, is\[\frac{1}{2}\]. If one of the directories is\[x=4,\]then the equation of the ellipse is
question_answer55) A line makes the same angle\[\theta \]with each of the x and z-axes. If the angle\[\beta ,\]which it makes with y-axis, is such that\[{{\sin }^{2}}\beta =3{{\sin }^{2}}\theta ,\]then\[\cos \theta \]equals
question_answer57) A line with direction cosines proportional to 2,1,2 meets each of the lines\[x=y+a=z\]and \[x+a=2y=2z\]. The coordinates of each of the points of intersection are given by
question_answer58) If the straight lines \[x=1+s,y=-3-\lambda s,\] \[z=1+\lambda \,s\]and\[x=\frac{t}{2},y=1+t,z=2-t,\]with parameters s and t respectively, are coplanar, then\[\lambda ,\]equals
question_answer59) The intersection of the spheres \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}+7x-2y-z=13\] and \[{{x}^{2}}+{{y}^{2}}+{{z}^{2}}-3x+3y+4z=8\] is the same as the intersection of one of the sphere and the plane
question_answer60) Let a, b and c be three non-zero vectors such that no two of these are collinear. If the vector \[a+2b\]is collinear with c and\[b+3c\]is collinear with a\[(\lambda \]being some non-zero scalar), then \[a+2b+6c\]equals
question_answer61) A particle is acted upon by constant forces \[4\hat{i}+\hat{j}-3\hat{k}\]and\[3\hat{i}+\hat{j}-\hat{k}\]which displace it from a point\[\hat{i}+2\hat{j}-3\hat{k}\]to the point \[5\hat{i}+4\hat{j}+\hat{k}\]. The work done in standard units by the forces is given by
question_answer62) If a, b, c are non-coplanar vectors and\[\lambda \]is a real number, then the vectors\[a+2b+3c,\lambda b+4c\]and\[(2\lambda -1)c\]are non-coplanar for
question_answer63) Let\[u,v,w\]be such that\[|u|=1,|v|=2,\]\[|w|=3.\]If the projection v along u is equal to that of w along u and\[v,w\]are perpendicular to each other, then\[|u-v+w|\]equals
question_answer64) Let a,b and c be non-zero vectors such that \[(a\times b)\times c=\frac{1}{3}|b||c|a.\]If\[\theta \]is the acute angle between the vectors b and c, then\[\sin \theta \]equals
question_answer65) Consider the following statements (1) Mode can be computed from histogram. (2) Median is not independent of change of scale. (3) Variance is independent of change of origin and scale. (4) Which of these is/are correct?
question_answer66) In a series of\[2n\]observations, half of them equal\[a\]and remaining half equal\[-a\]. If the standard deviation of the observations is 2, then \[|a|\] equals
question_answer67) The probability that A speaks truth is 4/5 while this probability for B is 3/4. The probability that they contradict each other when asked to speak on a fact, is
question_answer70) With two forces acting at a point, the maximum effect is obtained when their resultant is 4N. If they act at right angles, then their resultant is 3N. Then, the forces are
question_answer71) In a right angled \[\Delta ABC,\,\,\angle A={{90}^{\text{o}}}\] and sides a,b,c are respectively, 5 cm, 4 cm and 3 cm. If a force F has moments 0, 9 and 16 (in N cm) units respectively about vertices A, B and C, the magnitude of F is
question_answer72) Three forces P, Q and R acting along\[IA,IB\]and \[IC,\]where\[I\]is the incentre of a\[\Delta ABC,\]are in equilibrium. Then, P : Q : R is
question_answer73) A particle moves towards East from a point A to a point B at the rate of 4 km/h and then towards North from B to C at rate of 5 km/h. If AB = 12 km and BC = 5 km, then its average speed for its journey from A to C and resultant average velocity direct from A to C are respectively
question_answer74) A velocity 1/4 m/s is resolved into two components along OA and OB making angles \[30{}^\circ \]and\[45{}^\circ \]respectively with the given velocity, Then, the component along OB is
question_answer75) If\[{{t}_{1}}\]and\[{{t}_{2}}\]are the times of flight of two particles having the same initial velocity u and range R on the horizontal, then\[t_{1}^{2}+t_{2}^{2}\]is equal to