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The area of the region whose boundaries ...

The area of the region whose boundaries are defined by the curves y=2 cos x, y=3 tan x, and the y-axis is

A

`1+3" In "((2)/(sqrt(3)))` sq. units

B

`1+(3)/(2)" In "3-3" In "2` sq. units

C

`1+(3)/(2)" In "3-"In "2` sq. units

D

`" In "3-" In "2` sq. units

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To find the area of the region bounded by the curves \( y = 2 \cos x \), \( y = 3 \tan x \), and the y-axis, we will follow these steps: ### Step 1: Find the points of intersection We need to find the points where the curves intersect. This is done by setting the equations equal to each other: \[ 2 \cos x = 3 \tan x \] Substituting \(\tan x = \frac{\sin x}{\cos x}\): \[ 2 \cos x = 3 \frac{\sin x}{\cos x} \] Multiplying both sides by \(\cos x\) (assuming \(\cos x \neq 0\)): \[ 2 \cos^2 x = 3 \sin x \] Using the identity \(\sin^2 x + \cos^2 x = 1\), we can express \(\cos^2 x\) in terms of \(\sin x\): \[ 2(1 - \sin^2 x) = 3 \sin x \] This simplifies to: \[ 2 - 2 \sin^2 x = 3 \sin x \] Rearranging gives us a quadratic equation: \[ 2 \sin^2 x + 3 \sin x - 2 = 0 \] ### Step 2: Solve the quadratic equation Using the quadratic formula \( \sin x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \): Here, \( a = 2, b = 3, c = -2 \): \[ \sin x = \frac{-3 \pm \sqrt{3^2 - 4 \cdot 2 \cdot (-2)}}{2 \cdot 2} \] \[ = \frac{-3 \pm \sqrt{9 + 16}}{4} \] \[ = \frac{-3 \pm 5}{4} \] Calculating the two possible values: 1. \( \sin x = \frac{2}{4} = \frac{1}{2} \) (valid) 2. \( \sin x = \frac{-8}{4} = -2 \) (not valid) Thus, we have: \[ \sin x = \frac{1}{2} \implies x = \frac{\pi}{6} \] ### Step 3: Determine the area The area \( A \) between the curves from \( x = 0 \) to \( x = \frac{\pi}{6} \) is given by: \[ A = \int_0^{\frac{\pi}{6}} (2 \cos x - 3 \tan x) \, dx \] ### Step 4: Calculate the integral Calculating the integral: 1. The integral of \( 2 \cos x \) is \( 2 \sin x \). 2. The integral of \( 3 \tan x \) is \( 3 \ln |\sec x| \). Thus, we have: \[ A = \left[ 2 \sin x - 3 \ln |\sec x| \right]_0^{\frac{\pi}{6}} \] Calculating at the limits: At \( x = \frac{\pi}{6} \): \[ = 2 \sin\left(\frac{\pi}{6}\right) - 3 \ln\left|\sec\left(\frac{\pi}{6}\right)\right| \] \[ = 2 \cdot \frac{1}{2} - 3 \ln\left|\frac{2}{\sqrt{3}}\right| \] \[ = 1 - 3 \ln 2 + 3 \ln \sqrt{3} \] \[ = 1 - 3 \ln 2 + \frac{3}{2} \ln 3 \] At \( x = 0 \): \[ = 2 \sin(0) - 3 \ln|\sec(0)| = 0 - 3 \ln(1) = 0 \] Thus, the area \( A \) simplifies to: \[ A = 1 - 3 \ln 2 + \frac{3}{2} \ln 3 \] ### Final Answer The area of the region bounded by the curves is: \[ A = 1 - 3 \ln 2 + \frac{3}{2} \ln 3 \quad \text{(in square units)} \]

To find the area of the region bounded by the curves \( y = 2 \cos x \), \( y = 3 \tan x \), and the y-axis, we will follow these steps: ### Step 1: Find the points of intersection We need to find the points where the curves intersect. This is done by setting the equations equal to each other: \[ 2 \cos x = 3 \tan x \] ...
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Knowledge Check

  • The area of the region bounded by the curves y=x^(2) " and " x=y^(2) is

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    `1/3`
    B
    `1/2`
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    D
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  • The area of the region bounded by the curve y="sin"2x, y-axis and y=1 is :

    A
    1 sq. unit
    B
    `(1)/(2)` sq. unit
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    D
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