Question 511 Mark
The function $f ( x )=x-\frac{1}{x}, x \in R , x \neq 0$ is increasing
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If $y=x^2$, then the rate of change of demand ( $x$ ) of a commodity with respect to its price $(y)$ is $\frac{1}{2 x}$
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Optimal assignments are made in the Hungarian method to cells in the reduced matrix that contain a zero
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For Cost of Living Index Number CLI $=\frac{\sum I W}{\sum W}$, where $I=\frac{P_0}{P_1} \times 100$ and $w=p_0 q_0$
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Cyclical variation can occur several times in a year.
AnswerThis statement is
False.
Explanation:
Seasonal variation can occur several times in a year.
View full question & answer→Question 561 Mark
If $X \sim B(n, p)$ and $n=6$ and $P(X=4)=P(X=2)$, then $p=\frac{1}{2}$
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State whether the following statement is True or False:
A factor is an agent who is given the possession of goods and enters a contract for sale in his/her own name
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State whether the following statement is True or False:
Order and degree of differential equation are always positive integers.
View full question & answer→Question 591 Mark
$
\int_0^1 \frac{1}{2 x+5} d x=\log \left(\frac{7}{5}\right)
$
View full question & answer→Question 601 Mark
If $\int x e ^{2 x} dx$ is equal to $e ^{2 x} f ( x )+ c$, where $c$ is constant of integration, then $f ( x )$ is $\frac{2 x-1}{2}$.
AnswerFalse
Explanation:
$ \text { Let } I =\int x \cdot e ^{2 x } dx$
$= x \int e ^{2 x } \cdot dx -\int\left[\frac{ d }{ dx }( x ) \int e ^{2 x } \cdot dx \right] dx$
$= x \cdot \frac{ e ^{2 x }}{2}-\int 1 \cdot \frac{ e ^{2 x }}{2} \cdot dx$
$=\frac{ x }{2} e ^{2 x }-\frac{1}{2} \int e ^{2 x }+ c$
$=\frac{ x }{2} e ^{2 x }-\frac{1}{2} \cdot \frac{ e ^{2 x }}{2}+ c$
$= e ^{2 x }\left(\frac{ x }{2}-\frac{1}{4}\right)+ c$
$= e ^{2 x }\left(\frac{2 x -1}{4}\right)+ c $
$\therefore f(x)=\frac{2 x-1}{4}$
View full question & answer→Question 611 Mark
The function $f ( x )=\frac{3}{x}+10, x \neq 0$ is decreasing
View full question & answer→Question 621 Mark
If $y =10^{ x }+1$, then $\frac{ d y}{ d x}=10^{ x } \cdot \log 10$
View full question & answer→Question 631 Mark
To convert the assignment problem into maximization problem, the smallest element in the matrix is to deducted from all other elements
View full question & answer→Question 641 Mark
The three types of Index numbers are
i. Price Index Number
ii. Quantity Index Number
iii. Value Index Number
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State whether the following statement is True or False:
Seasonal variation can be observed over several years
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If $f ( x )=\begin{array}{ll} k x(1-x), & \text { for } 0
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State whether the following statement is True or False:
The trade discount is first calculated on the catalogue (list) price
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State whether the following statement is True or False:
The integrating factor of the differential equation $\frac{ d y}{ d x}-y= x$ is $e ^{- x }$
View full question & answer→Question 691 Mark
$
\int_0^{ a } 3 x^2 d x=27, \text { then } a =2.5
$
View full question & answer→Question 701 Mark
The proper substitution for $\int x\left(x^x\right)^x(2 \log x+1) d x$ is $\left(x^x\right)^x= t$
AnswerTrue
Explanation:
Let $I=\int x\left(x^x\right)^x(2 \log x+1) d x$
Put $\left( x ^{ x }\right)^{ x }= t$
Taking logarithm of both sides, we get
$ \log \left( x ^{ x }\right)^{ x }=\log t$
$\therefore x ^2 \cdot \log x =\log t $
Differentiating w.r.t. $x$, we get
$ x ^2 \cdot \frac{1}{ x }+(\log x ) \cdot 2 x =\frac{1}{ t } \cdot \frac{ dt }{ dx }$
$\therefore( x +2 x \log x ) dx =\frac{1}{ t } \cdot dt$
$\therefore x (1+2 \log x ) dx =\frac{1}{ t } \cdot dt $
$\therefore I =\int t \cdot \frac{1}{ t } \cdot dt =\int 1 \cdot dt = t + c =\left( x ^{ x }\right)^{ x }+ c$
View full question & answer→Question 711 Mark
An absolute maximum must occur at a critical point or at an end point.
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If $y =\log (\log x )$, then $\frac{ d y}{ d x}=\log x$
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The objective of an assignment problem is to assign number of jobs to equal number of persons at maximum cost
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Walsh's Price Index Number is given by $\frac{\sum p_1 \sqrt{q_0 q_1}}{\sum p_0 \sqrt{q_0 q_1}} \times 100$
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State whether the following statement is True or False:
The secular trend component of time series represents irregular variations
View full question & answer→Question 761 Mark
In sequencing problem each machine is of different type
View full question & answer→Question 771 Mark
If $y = e ^{ x }$, then $\frac{ d ^2 y}{ d x^2}= e ^{ x }$
View full question & answer→Question 781 Mark
In sequencing problem each job once started on any machine must be processed still its completion
View full question & answer→Question 791 Mark
The function $y = cx$ is the solution of differential equation $\frac{ d y}{ d x}=\frac{y}{x}$
View full question & answer→Question 801 Mark
$
\int \sqrt{1+x^2} \cdot x d x=\frac{1}{3}\left(1+x^2\right)^{\frac{3}{2}}+ c
$
View full question & answer→Question 811 Mark
If $x =5 m , y = m$, where $m$ is parameter, then $\frac{ d y}{ d x}=\frac{1}{5}$
View full question & answer→Question 821 Mark
In sequencing problem the processing times are dependent of order of processing the jobs on machine
View full question & answer→Question 831 Mark
X is the number obtained on upper most face when a die is thrown, then E(x) = 3.5
View full question & answer→Question 841 Mark
After applying elementary transformation $R_1-3 R_2$ on matrix $\left[\begin{array}{cc}3 & -2 \\ 1 & 4\end{array}\right]$ we get $\left[\begin{array}{cc}0 & -12 \\ 1 & 4\end{array}\right]$
View full question & answer→Question 851 Mark
State whether the following statement is True or False:
If equation of regression lines are $3 x+2 y-26=0$ and $6 x+y-31=0$, then mean of $X$ is 7
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$p \vee \sim p \equiv \sim c$
View full question & answer→Question 871 Mark
If O(A) = m × n and O(B) = n × p with m ≠ p, then BA exists but AB does not exist.
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State whether the following statement is True or False:
If $u=x-a$ and $v=y-b$ then $b_{x y}=b_{u v}$
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State whether the following statement is True or False:
An annuity where payments continue forever is called perpetuity
View full question & answer→Question 901 Mark
Mathematical identities are true statements
View full question & answer→Question 911 Mark
$\left[\begin{array}{ccc}2 & 0 & 0 \\ 3 & -1 & 0 \\ -7 & 3 & 1\end{array}\right]$ is a skew symmetric matrix
View full question & answer→Question 921 Mark
State whether the following statement is True or False:
The following data is not consistent: $b_{y x}+b_{x y}=1.3$ and $r=0.75$
View full question & answer→Question 931 Mark
State whether the following statement is True or False:
Annuity contingent begins and ends on certain fixed dates
View full question & answer→Question 941 Mark
The dual of $(p \wedge q) \vee \sim q$ is $(p \vee q) \wedge \sim q$
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Matrix $\left[\begin{array}{ccc} a & b & c \\ p & q & r \\ 2 a - p & 2 b - q & 2 c - r \end{array}\right]$ is a singular
View full question & answer→Question 961 Mark
State whether the following statement is True or False:
If $b_{x y}<0$ and $b_{y x}<0$ then ' $r$ ' is $>0$
View full question & answer→Question 971 Mark
State whether the following statement is True or False:
The future value of an annuity is the accumulated values of all instalments
View full question & answer→Question 981 Mark
p ↔ q is false when p and q have different truth values
View full question & answer→Question 991 Mark
If $A=\left[\begin{array}{ccc}1 & 2 & -5 \\ 2 & -3 & 4 \\ -5 & 4 & 9\end{array}\right]$, then $A^{\top}=A$
View full question & answer→Question 1001 Mark
State whether the following statement is True or False:
Correlation analysis is the theory of games
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