Question
Write the angle between the curves $y = e^{-x}$ and $y = e^x$ at their point of intersections.

Answer

The given equation of curve are,
$y = e^{-x}...(1)$
$y = e^x...(2)$
Solving $(1)$ and $(2)$
$\text{y}=\frac{1}{\text{e}^\text{x}}=\frac{1}{\text{y}}$
$\Rightarrow\text{y}^2=1$
$\Rightarrow\text{y}=\pm1$
From $(2)$
$\pm1=\text{e}^\text{x}$
$\Rightarrow\text{x}=0$
So, the point of intersection is $P = (0, 1)$ and $Q = (0, -1).$
Slope of $(2)$
$\text{m}_2=\frac{\text{dy}}{\text{dx}}=\text{e}^{\text{x}}$
$\therefore\text{m}_2\text{ at }\text{P}=1\text{ and }\text{m}_2\text{ at }\text{Q}=1$
$\therefore\text{m}_1\times\text{m}_2=-1\times1=-1$
The angle between the curves is $90^\circ$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

If the vertices A, B, C of a triangle ABC are (1, 2, 3), (-1, 0, 0), (0, 1, 2), respectively, then find $\angle\text{ABC}.[\angle\text{ABC is the angle between the vectors}\ \overrightarrow{\text{BA}}\ \text{and} \ \overrightarrow{\text{BC}}].$
By using the properties of definite integrals, evaluate the integral $\int\limits_0^{\frac{\pi }{2}} {\frac{{\sin x - \cos x}}{{1 + \sin x\cos x}}} dx$
Express $\overrightarrow{\text{AB}}$ in terms of unit vectors $\hat{\text{i}}\text{ and }\hat{\text{j}}$, when the point is:A(-6, 3), B(-2, -5)
Find $\Big|\overrightarrow{\text{AB}}\Big|$
Without using the derivative show that the function f(x) = 7x - 3 is strictly increasing function on R.
Show that the three lines with direction cosines $\frac{12}{13},\ \frac{-3}{13},\ \frac{-4}{13},\ \frac{4}{13},\ \frac{12}{13},\ \frac{3}{13},\ \frac{3}{13},\ \frac{-4}{13},\ \frac{12}{13}$ are mutually perpendicular.
Using properties of determinants, prove the following:
$\begin{vmatrix} 3a & -a + b & -a + c \\ a - b & 3b & c - b \\ a - c & b - c & 3c \end{vmatrix} = 3(a + b + c) (ab + bc + ca) $
Differentiate the following functions with respect to x:
$\text{e}^{\sin\sqrt{\text{x}}}$
Prove that the relation R in the set $\text{A } = (1, 2, 3, 4, 5)$ given by $\text{R} = (\text{a, b)} : |\text{a-b|} \text{is even},$  is an equivalence relation.
By using properties of determinants, show that:
$\begin{vmatrix}y+k&y&y\\y&y+k&y\\y&y&y+k\end{vmatrix}=k^2(3y+k)$
On Q, the set of all rational numbers a binary operation * is defined by $\text{a}\ ^*\ \text{b}=\frac{\text{a}+\text{b}}{2}.$ Show that * is not associative on Q.