Exponential Functions

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jee-main 2014 Q81 Exponential Equation Solving
If $f ( x ) = \left( \frac { 3 } { 5 } \right) ^ { x } + \left( \frac { 4 } { 5 } \right) ^ { x } - 1 , x \in R$, then the equation $f ( x ) = 0$ has:
(1) No solution
(2) More than two solutions
(3) One solution
(4) Two solutions
jee-main 2019 Q79 Functional Equation with Exponentials
Let $f ( x ) = a ^ { x }$ $( a > 0 )$ be written as $f ( x ) = f _ { 1 } ( x ) + f _ { 2 } ( x )$, where $f _ { 1 } ( x )$ is an even function and $f _ { 2 } ( x )$ is an odd function. Then $f _ { 1 } ( x + y ) + f _ { 1 } ( x - y )$ equals:
(1) $2 f _ { 1 } ( x ) f _ { 1 } ( y )$
(2) $2 f _ { 1 } ( x + y ) f _ { 1 } ( x - y )$
(3) $2 f _ { 1 } ( x ) f _ { 2 } ( y )$
(4) $2 f _ { 1 } ( x + y ) f _ { 2 } ( x - y )$
jee-main 2019 Q79 Functional Equation with Exponentials
Let $\sum _ { k = 1 } ^ { 10 } f ( a + k ) = 16 \left( 2 ^ { 10 } - 1 \right)$, where the function $f$ satisfies $f ( x + y ) = f ( x ) f ( y )$ for all natural numbers $x , y$ and $f ( 1 ) = 2$. Then the natural number ' $a$ ' is:
(1) 3
(2) 16
(3) 4
(4) 2
jee-main 2020 Q73 Limit Evaluation
$\lim _ { x \rightarrow 2 } \frac { 3 ^ { x } + 3 ^ { 3 - x } - 12 } { 3 ^ { - \frac { x } { 2 } } - 3 ^ { 1 - x } }$ is equal to
jee-main 2021 Q63 Exponential Equation Solving
The minimum value of $f ( x ) = a ^ { a ^ { x } } + a ^ { 1 - a ^ { x } }$, where $a , x \in R$ and $a > 0$, is equal to:
(1) $a + 1$
(2) $2 a$
(3) $a + \frac { 1 } { a }$
(4) $2 \sqrt { a }$
jee-main 2023 Q61 Exponential Equation Solving
The equation $e^{4x} + 8e^{3x} + 13e^{2x} - 8e^x + 1 = 0, x \in R$ has:
(1) four solutions two of which are negative
(2) two solutions and both are negative
(3) no solution
(4) two solutions and only one of them is negative
jee-main 2023 Q61 Exponential Equation Solving
Let $S = \{x : x \in \mathbb{R}$ and $\left(\sqrt{3} + \sqrt{2}\right)^{x^2 - 4} + \left(\sqrt{3} - \sqrt{2}\right)^{x^2 - 4} = 10\}$. Then $n(S)$ is equal to
(1) 2
(2) 4
(3) 6
(4) 0
jee-main 2023 Q76 Parameter Determination from Conditions
Let $f : \mathbb { R } \rightarrow \mathbb { R }$ be a function defined by $f ( x ) = \log _ { \sqrt { m } } \{ \sqrt { 2 } ( \sin x - \cos x ) + m - 2 \}$, for some $m$, such that the range of $f$ is $[ 0,2 ]$. Then the value of $m$ is $\_\_\_\_$.
(1) 5
(2) 3
(3) 2
(4) 4
jee-main 2024 Q68 Limit Evaluation
$\lim _ { x \rightarrow 0 } \frac { e - ( 1 + 2 x ) ^ { \frac { 1 } { 2 x } } } { x }$ is equal to
(1) 0
(2) $\frac { - 2 } { e }$
(3) e
(4) $e - e ^ { 2 }$
jee-main 2024 Q76 Parameter Determination from Conditions
Let $f: R \rightarrow R$ be defined $f(x) = ae^{2x} + be^x + cx$. If $f(0) = -1$, $f'(\log_e 2) = 21$ and $\int_0^{\log 4} (f(x) - cx)\, dx = \frac{39}{2}$, then the value of $|a + b + c|$ equals:
(1) 16
(2) 10
(3) 12
(4) 8
jee-main 2024 Q85 Limit Evaluation
If $\alpha = \lim _ { x \rightarrow 0 ^ { + } } \left( \frac { \mathrm { e } ^ { \sqrt { \tan x } } - \mathrm { e } ^ { \sqrt { x } } } { \sqrt { \tan x } - \sqrt { x } } \right)$ and $\beta = \lim _ { x \rightarrow 0 } ( 1 + \sin x ) ^ { \frac { 1 } { 2 } \cot x }$ are the roots of the quadratic equation $a x ^ { 2 } + b x - \sqrt { \mathrm { e } } = 0$, then $12 \log _ { \mathrm { e } } ( \mathrm { a } + \mathrm { b } )$ is equal to $\_\_\_\_$
jee-main 2025 Q7 Algebraic Simplification and Expression Manipulation
If $f ( x ) = \frac { 2 ^ { x } } { 2 ^ { x } + \sqrt { 2 } } , \mathrm { x } \in \mathbb { R }$, then $\sum _ { \mathrm { k } = 1 } ^ { 81 } f \left( \frac { \mathrm { k } } { 82 } \right)$ is equal to
(1) $1.81 \sqrt { 2 }$
(2) 41
(3) 82
(4) $\frac { 81 } { 2 }$
jee-main 2025 Q11 Limit Evaluation
If $\lim _ { x \rightarrow \infty } \left( \left( \frac { \mathrm { e } } { 1 - \mathrm { e } } \right) \left( \frac { 1 } { \mathrm { e } } - \frac { x } { 1 + x } \right) \right) ^ { x } = \alpha$, then the value of $\frac { \log _ { \mathrm { e } } \alpha } { 1 + \log _ { \mathrm { e } } \alpha }$ equals:
(1) $e ^ { - 1 }$
(2) $\mathrm { e } ^ { 2 }$
(3) $e ^ { - 2 }$
(4) e
taiwan-gsat 2021 QD 5 marks Intersection and Distance between Curves
On the coordinate plane, $\Gamma$ is a square with side length 4, centered at the point $(1,1)$, with sides parallel to the coordinate axes. The graph of the function $y = a \times 2 ^ { x }$ intersects $\Gamma$, where $a$ is a real number. The maximum possible range of $a$ is (22)(23) $\leq a \leq$ (24).
taiwan-gsat 2023 Q10 5 marks Applied/Contextual Exponential Modeling
An organization introduced two different nutrients into culture dishes A and B at 12 o'clock. At this time, the bacterial counts in dishes A and B are $X$ and $Y$ respectively. The quantity in dish A doubles every 3 hours; for example, at 3 PM the quantity in A is $2X$. The quantity in dish B doubles every 2 hours; for example, at 2 PM the quantity in B is $2Y$, and at 4 PM the quantity in B is $4Y$. Part of the measurement results are recorded in the table below. At 6 PM, the organization measured that the quantities in dishes A and B are the same. To estimate the bacterial quantities in dishes A and B from 12 o'clock to 12 midnight using an exponential growth model, select the correct options.
Time (o'clock)12131415161718192021222324
Quantity in A$X$$2X$
Quantity in B$Y$$2Y$$4Y$

(1) $X > Y$ (2) At 1 PM, the quantity in A is $\frac{4}{3}X$ (3) At 3 PM, the quantity in B is $3Y$ (4) At 7 PM, the quantity in B is 1.5 times that of A (5) At 12 midnight, the quantity in B is 2 times that of A
taiwan-gsat 2024 Q11 5 marks Applied/Contextual Exponential Modeling
Over the past five years, a country's total carbon emissions decreased from $X$ billion metric tons of CO2 equivalent (CO2e) in year 1 to $Y$ billion metric tons of CO2 equivalent (CO2e) in year 5, achieving an average annual carbon reduction of 5\%, that is, $Y = ( 1 - 0.05 ) ^ { 4 } X$. The five-year carbon emission totals and annual growth rates are recorded in the following table, where Year $n$ carbon emission growth rate $= \frac { \text {(Year } n \text { carbon emission total)} - \text {(Year } n - 1 \text { carbon emission total)} } { \text {Year } n - 1 \text { carbon emission total} }$, $n = 2,3,4,5$.
Year 1Year 2Year 3Year 4Year 5
\begin{tabular}{ c } Carbon Emission Total
$($ billion metric tons $\mathrm { CO } 2 \mathrm { e } )$
& $X$ & $A$ & $B$ & $C$ & $Y$ \hline Annual Carbon Emission Growth Rate & & - 0.07 & $p$ & $q$ & $r$ \hline \end{tabular}
Select the correct options.
(1) $A = 0.93 X$
(2) $Y \leq 0.8 X$
(3) $\frac { - 0.07 + p + q + r } { 4 } = - 0.05$
(4) $\sqrt [ 4 ] { \frac { Y } { X } } - 1 = - 0.05$
(5) $0.93 ( 1 + p ) ( 1 + q ) ( 1 + r ) = ( 0.95 ) ^ { 4 }$
taiwan-gsat 2025 Q6 8 marks True/False or Multiple-Statement Verification
Let the exponential function $f(x) = 1.2^{x}$. Select the correct options.
(1) $f(0) > 0$
(2) $f(10) > 10$
(3) On the coordinate plane, the graph of $y = 1.2^{x}$ intersects the line $y = x$
(4) On the coordinate plane, the graphs of $y = 1.2^{x}$ and $y = \log(1.2^{x})$ are symmetric about the line $y = x$
(5) For any positive real number $b$, $\log_{1.2} b \neq 1.2^{b}$
taiwan-gsat 2025 Q8 5 marks Algebraic Simplification and Expression Manipulation
Consider points $P ( x , y )$ on the coordinate plane satisfying the equation $\frac { 2 ^ { x ^ { 2 } } } { 8 } = \frac { 4 ^ { x } } { 2 ^ { y ^ { 2 } } }$. Select the correct options.
(1) When $x = 3$, there are 2 distinct solutions satisfying this equation
(2) If point $( a , b )$ satisfies this equation, then point $( - a , - b )$ also satisfies this equation
(3) All possible points $P ( x , y )$ form a circle
(4) Point $P ( x , y )$ may lie on the line $x + y = 4$
(5) For all possible points $P ( x , y )$, the maximum value of $x - y$ is $1 + 2 \sqrt { 2 }$
taiwan-gsat 2025 Q18 3 marks Applied/Contextual Exponential Modeling
It is known that UVI values have an exponential relationship with altitude: for every 300-meter increase in altitude, the UVI value increases by 4\% of the value before the increase. At ground level, the ultraviolet radiation received from the sun is 400 joules per square meter. At a mountain 4500 meters above ground level, the UVI value of the ultraviolet radiation received is which of the following options? (Single choice question, 3 points)
(1) $4 ( 1 + 0.04 \times 15 )$
(2) $4 \left( 1 + 0.04 ^ { 15 } \right)$
(3) $4 ( 1 + 0.04 ) ^ { 15 }$
(4) $4 \times 100 ( 1 + 0.04 ) ^ { 15 }$
(5) $4 \times 100 \left( 1 + 0.04 ^ { 45 } \right)$
turkey-yks 2012 Q8 Exponential Equation Solving
Let x be a real number such that
$$( \sqrt { 7 } + \sqrt { 3 } ) ^ { x } = 4$$
Given this, which of the following is the expression $( \sqrt { 7 } - \sqrt { 3 } ) ^ { x }$ equal to?
A) $2 ^ { - x }$
B) $2 ^ { - x + 1 }$
C) $4 ^ { x }$
D) $4 ^ { x - 1 }$
E) $4 ^ { x + 1 }$
turkey-yks 2012 Q13 Exponential Equation Solving
The operation $\Delta$ is defined on the set of real numbers for all real numbers a and b as
$$a \Delta b = a ^ { 2 } + 2 ^ { b }$$
Given that $2 \Delta ( 1 \Delta x ) = 12$, what is x?
A) $\frac { 1 } { 2 }$
B) $\frac { 2 } { 3 }$
C) $\frac { 1 } { 4 }$
D) 1
E) 2
turkey-yks 2014 Q40 True/False or Multiple-Statement Verification
A function f is defined on the set of real numbers as
$$f ( x ) = 1 + e ^ { - x }$$
Accordingly, I. The range of function f is $( 1 , \infty )$. II. Function f is decreasing on its domain. III. The line $y = 0$ is a horizontal asymptote of function f. Which of the following statements are true?
A) Only II
B) Only III
C) I and II
turkey-yks 2015 Q13 Exponential Equation Solving
For integers a and b
$$\frac { 6 ^ { a ^ { 2 } + b ^ { 2 } } } { 9 ^ { a b } } = 96$$
Given that, what is the product $\mathbf { a } \cdot \mathbf { b }$?
A) 1 B) 2 C) 3 D) 4 E) 6
turkey-yks 2017 Q8 Exponential Equation Solving
$$\begin{aligned} & 4 ^ { x } + 4 ^ { y } = 10 \\ & 4 ^ { x } - 4 ^ { y } = 8 \end{aligned}$$
Accordingly, what is the value of the expression $\mathbf { 2 } ^ { \mathbf { x } + \mathbf { y } }$?
A) 2 B) 3 C) 4 D) 5 E) 6
turkey-yks 2019 Q25 Ordering and Comparing Exponential Values
Below; the graphs of linear functions $f$, $g$ and $h$ are shown in Figure 1 on a rectangular coordinate plane divided into unit squares, and the derivatives of these functions are shown in Figure 2.
Accordingly; what is the correct ordering of $f ( 0 ) , g ( 0 )$ and $h ( 0 )$?
A) $\mathrm { f } ( 0 ) < \mathrm { h } ( 0 ) < \mathrm { g } ( 0 )$
B) $g ( 0 ) < f ( 0 ) < h ( 0 )$
C) $g ( 0 ) < h ( 0 ) < f ( 0 )$
D) $h ( 0 ) < f ( 0 ) < g ( 0 )$
E) $h ( 0 ) < g ( 0 ) < f ( 0 )$