154
4154
2027
1354
Correct answer is D
P(A)=16,P(T)=19
Probability that only one of them will hit the target = P(A)×P(ˉT)+P(ˉA)×P(T)
Where P(ˉT) is the probability that Tunde will not hit the target and P(ˉA) is the probability that Atta will not hit the target
P(ˉT)=1−19=89
P(ˉA)=1−16=56
Pr(only one) =(16×89)+(56×19)=427+554
∴ pr (only one) = \frac{13}{54}
A function f is defined by f :x→\frac{x + 2}{x - 3},x ≠ 3.Find the inverse of f .
\frac{x + 3}{x - 2},x ≠ 2
\frac{x - 3}{x + 2},x ≠ -2
\frac{3x - 2}{x+1},x ≠ -1
\frac{3x + 2}{x - 1},x ≠ 1
Correct answer is D
f :x→\frac{x + 2}{x - 3},x ≠ 3, f = ?
Let f :x=y
y=\frac{x + 2}{x - 3}
=x+2=y(x-3)
=x-xy=-3y-2
=x(1-y)=-3y-2
=x=\frac{-3y - 2}{1 - y}=\frac{-(3y + 2)}{- (y - 1)}
=x=\frac{3y + 2}{y - 1}
∴f ^{-1} : x=\frac{3x + 2}{x - 1},x ≠ 1
\frac{1}{6}
\frac{4}{7}
\frac{4}{21}
\frac{3}{7}
Correct answer is B
P(X⋃Y)=\frac{5}{8}
P(X⋂Y)=P(X)\times P(Y)
Since X and Y are independent events, the probability of their union (X ⋃ Y) can be calculated as:
P(X⋃Y)=P(X)+P(Y)-P(X⋂Y)
=\frac{5}{8}=\frac{1}{8}+P(Y)-\frac{1}{8}\times P(Y)
=\frac{5}{8}-\frac{1}{8}=P(Y)-\frac{1}{8}\times P(Y)
=\frac{1}{2}=P(Y)(1-\frac{1}{8})
=\frac{1}{2}=P(Y)(\frac{7}{8})
=P(Y)=\frac{1}{2}÷\frac{7}{8}
∴P(Y)=\frac{1}{2}x\frac{8}{7}=\frac{4}{7}
Given that y^2 + xy = 5,find \frac{dy}{dx}
\frac{y}{2y + x}
\frac{-y}{2y + x}
\frac{-y}{2y - x}
\frac{y}{2y + x}
Correct answer is B
y^2 + xy = 5
By implicit differentiation
=2y\frac{dy}{dx}+y+x\frac{dy}{dx}=0
=2y\frac{dy}{dx}+x\frac{dy}{dx}=-y
Factor out \frac{dy}{dx}
=\frac{dy}{dx}(2y+x)=-y
∴\frac{dy}{dx}=\frac{-y}{2y + x}
A linear transformation on the oxy plane is defined by P : (x, y) → (2x + y, -2y). Find P^2
\begin{bmatrix} 4&0\\1&4\end{bmatrix}
\begin{bmatrix} 4&4\\0&0\end{bmatrix}
\begin{bmatrix} 4&0\\0&4\end{bmatrix}
\begin{bmatrix} 4&1\\0&4\end{bmatrix}
Correct answer is C
P : (x, y) → (2x + y, -2y)
p\begin{bmatrix} x\\y\end{bmatrix}=\begin{bmatrix} 2x & y\\0 &-2y\end{bmatrix}
\therefore p = \begin{bmatrix} 2 & 1\\0 &-2\end{bmatrix}
\therefore p^2 = \begin{bmatrix} 2&1\\0&-2\end{bmatrix} \begin{bmatrix} 2&1\\0&-2\end{bmatrix} = \begin{bmatrix} 4&0\\0&4\end{bmatrix}