Recent questions tagged maths

If the $2^{nd},5^{th}$ and $9^{th}$ terms of a non-constant A.P. are in G.P., then the common ratio of this G.P. is:

asked Mar 16, 2017 by meena.p

1 answer

If the number of terms in the expansion of $\bigg(1- \large\frac{2}{x}+\frac{4}{x^2}\bigg)^n,x \neq 0,$ is 28, then the sum of the coefficients of all the terms in this expansion, is

asked Mar 15, 2017 by meena.p

1 answer

If all the words (with or without meaning) having five letters, formed using the letters of the word SMALL and arranged as in a dictionary; then the position of the word SMALL is:

asked Mar 15, 2017 by meena.p

1 answer

The system of linear equations <br> $x + \lambda y - z = 0 \\\lambda x - y - z = 0 \\x + y - \lambda z = 0$ has a non-trivial solution for:

asked Mar 15, 2017 by meena.p

1 answer

If $A =\begin{bmatrix} 5a & -b \\ 3 & 2 \end{bmatrix}$ and $A \;adj A = AA^T$, then $5a+b$ is equal to

asked Mar 15, 2017 by meena.p

1 answer

The sum of all real values of x satisfying the equation $(x^2-5x+5)^{x^2+4x-60}=1$ is :

asked Mar 15, 2017 by meena.p

1 answer

A value of $\theta$ for which $ \large\frac{2+3 i \sin \theta}{1- 2 i \sin \theta}$ is purely imaginary , is

asked Mar 15, 2017 by meena.p

1 answer

If $f(x) +2y \bigg(\large\frac{1}{x}\bigg)$$=3x,x \neq 0$ and $S=\{x \in R:f(x)=f(-x)\}$ then S:

asked Mar 15, 2017 by meena.p

1 answer

If the points $(1,1,p)$ and $(-3,0,1)$ are at equidistant from the plane $\overrightarrow {r} . (3 \hat {i} +4 \hat {j} -12 \hat {k}) + 13 = 0, $ then find the value of p.

asked Dec 28, 2016 by priyanka.c

1 answer

Form the differential equation of the family of circles in the first quadrant which touch the coordinate axes.

asked Dec 27, 2016 by priyanka.c

1 answer

An oil company has two depots A and B with capacities of 7000 L and 4000 L respectively. The company is to supply oil to three petrol pumps, D, E and F whose requirements are 4500L, 3000L and 3500L respectively. Assuming that the transportation cost of 10 litres of oil is Rs 1 per km, How should the delivery be scheduled in order that the transportation cost is minimum ? What is the minimum cost? The distance (In km) between the depots and the petrol pumps is given in the following table :

asked Dec 27, 2016 by priyanka.c

1 answer

Suppose a girl throws a die. If she throws a 5 or 6, she tosses a coin 3 times and notes the number of heads. If she gets 1, 2, 3 or 4, she tosses a coin once and notes whether a head or tail is obtained. If she obtained exactly one head, what is the probability that she threw 1, 2, 3 or 4 with a die?

asked Dec 27, 2016 by priyanka.c

1 answer

Find the area of the region $\{ (x,y) : 0 \leq y \leq x^2, 0 \leq y \leq x+2 , 0 \leq x \leq 3\}$

asked Dec 27, 2016 by priyanka.c

1 answer

Find the image of the point (1, 3. 4) in the plane $x-y+z =5$. Hence show that the image lies on the plane $x -2y +z -7 = 0$

asked Dec 27, 2016 by priyanka.c

1 answer

Radioactive wastes is to be disposed of in full enclosed lead boxes of inner volume $200 cm^3$. The base of the box has dimension in the ratio 2:1 . What is the inner length of the box. Find the minimum inner surface area of the box.

asked Dec 22, 2016 by priyanka.c

1 answer

Rent -a-car has three different makes of vehicles P, Q and R for hire. These cars are located at stations A and B on either side of a city. Some cars are being rented. In total they have 150 cars. At station A, they have 20% of P, 40% of Q and 30% of R which is 46 cars in total. At station B they have 40% of P, 20% of Q and 50% of R which is 54 cars in total. How many of each cars types does Rent-a -car have ?

asked Dec 22, 2016 by priyanka.c

1 answer

Integrate $\begin{align} \int \frac{\sin(x+a)}{\sin (x+b)} dx\end{align} $

asked Dec 22, 2016 by priyanka.c

1 answer

Express the matrix $A = \begin{bmatrix} 3 & 2 & 3 \\ 4 & 5 & 3 \\ 2 & 4 & 5 \end{bmatrix}$ as the sum of a symmetric and a skew symmetric matrix.

asked Dec 22, 2016 by priyanka.c

1 answer

Assume that each child born is equally likely to be a boy or a girl. If a family has two children, what is the conditional probability that both are girls given that
(a) The youngest is a girl.
(b) At least one is a girl.
Pre-natal * determination is a crime. What will you do if you come to know that some of your known is indulging in pre-natal * determination ?

asked Dec 22, 2016 by priyanka.c

1 answer

Evaluate $\begin{align} \int \limits_{-1}^{3/2} |x \sin {\pi \; x}| dx \end{align}$

asked Dec 21, 2016 by priyanka.c

1 answer

Find the condition that the curves $2x= y^2$ and $2xy = k $ intersect orthogonally.

asked Dec 21, 2016 by priyanka.c

1 answer

Differentiate $x ^{\sin ^{-1} x}$ w.r.t $\sin^{-1} x$

asked Dec 21, 2016 by priyanka.c

1 answer

For what value of $a$ and $b$ is the function $f(x) = \begin{cases} x^2 ,& x \leq c \\ ax+b , & x> c \end{cases} $ is differentiable at $x=c$

asked Dec 21, 2016 by priyanka.c

1 answer

Evaluate : $\begin{vmatrix} a & b-c & c+b \\ a+c & b & c-a \\ a-b & b+a & c \end{vmatrix} $

asked Dec 21, 2016 by priyanka.c

1 answer

On the set $R -\{ -1\} $ a binary operation $\ast$ is defined by $a \ast b = a + b + ab$ for all $a,b \in R - \{-1\}$. Prove that $\ast$ is commutative as well as associative on $R -\{-1\}$. Find the identity element on $\ast$ if any.

asked Dec 21, 2016 by priyanka.c

1 answer

Evaluate : $\tan \begin{bmatrix} \frac{\pi}{4} + \frac{1}{2} \cos^{-1} \frac{a}{b} \end{bmatrix} + \tan \begin{bmatrix} \frac{\pi}{4} - \frac{1}{2} \cos^{-1} \frac{a}{b} \end{bmatrix}$

asked Dec 21, 2016 by priyanka.c

1 answer