Use the arc length formula to find the length of the curve
y = (2 − x^2)^(1/2)
0 ≤ x ≤ 1.
Check your answer by noting that the curve is part of a circle.
y = (2 - x^2)^(1/2)
y^2 = 2 - x^2
2y * dy = -2x * dx
y * dy = -x * dx
dy/dx = -x / y
Arclength is the integral of:
sqrt(1 + (dy/dx)^2) * dx
sqrt(1 + (-x/y)^2) * dx =>
sqrt(1 + x^2 / y^2) * dx =>
sqrt((y^2 + x^2) / y^2) * dx =>
sqrt((x^2 + 2 - x^2) / (2 - x^2)) * dx =>
sqrt(2 / (2 - x^2)) * dx =>
sqrt(2) * dx / sqrt(2 - x^2)
x = sqrt(2) * sin(t)
dx = sqrt(2) * cos(t) * dt
sqrt(2) * sqrt(2) * cos(t) * dt / sqrt(2 - 2sin(t)^2) =>
2 * cos(t) * dt / sqrt(2 * (1 - sin(t)^2)) =>
2 * cos(t) * dt / sqrt(2 * cos(t)^2)) =>
2 * cos(t) * dt / (sqrt(2) * cos(t)) =>
sqrt(2) * dt
Integrate
sqrt(2) * t + C
Solve for t
x / sqrt(2) = sin(t)
t = arcsin(x / sqrt(2))
sqrt(2) * arcsin(x / sqrt(2)) + C
From 0 to 1
sqrt(2) * arcsin(1 / sqrt(2)) - sqrt(2) * arcsin(0 / sqrt(2)) =>
sqrt(2) * arcsin(sqrt(2)/2) - sqrt(2) * arcsin(0) =>
sqrt(2) * (pi/4) - sqrt(2) * 0 =>
(sqrt(2)/4) * pi
Use The Arc Length Formula
dy/dx = -x/(2 - x^2)^(1/2).
So, √[1 + (dy/dx)^2]
= √[1 + x^2/(2 - x^2)]
= √[((2 - x^2) + x^2)/(2 - x^2)]
= √2 / √(2 - x^2).
Hence, the arc length equals
∫(x = 0 to 1) √2 dx / √(2 - x^2)
= √2 arcsin(x/√2) {for x = 0 to 1}
= π√2 / 4.
Double check:
Note that the arc (with radius √2) is between 0 and 45 degrees (that is 1/8-th of the full circle).
So, the length equals (1/8) 2π * √2 = π√2 / 4.
I hope this helps!
y = √(2 - x^2)
dy/dx = - x /√(2 - x^2)
(dy/dx)^2 = x^2 /(2 - x^2)
1 + (dy/dx)^2 = ( 2 - x^2 + x^2) / (2 - x^2) = 2 / (2 - x^2) = 1 / (1 - (x^2/2))
SQRT [ 1 + (dy/dx)^2 ] = 1 /√( 1 - (x/√2)^2 )
arc length. s = ∫ dx /√( 1 - (x/√2)^2 ) from 0 to 1
let x/√2 = sin(t) when x = 0, t = 0 and when x = 1, t = π/4
dx = √2 cos(t) dt
s = ∫√2 cos(t) dt /√( 1 - sin^2(t) ) from 0 to π/4
= ∫√2 dt from 0 to π/4
= √2 t from 0 to π/4
= √2π/4
The given curve is y = √(2 - x^2)
=> y^2 = 2 - x^2
=> x^2 + y^2 = 2
This is eqn of circle with radius √2
we are looking circumference of 1/8 of circle ( 0 to 2π is full circle and 0 to π/4 is 1/8 circle)
C = 1/8(2π√2) = 1/4(√2π)
i'm specific that each females has their determination yet anatomically the exhilaration centres of a girl are in general placed interior in basic terms 2 inches of the front and subsequently technique beats length everythime.
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Verified answer
y = (2 - x^2)^(1/2)
y^2 = 2 - x^2
2y * dy = -2x * dx
y * dy = -x * dx
dy/dx = -x / y
Arclength is the integral of:
sqrt(1 + (dy/dx)^2) * dx
sqrt(1 + (-x/y)^2) * dx =>
sqrt(1 + x^2 / y^2) * dx =>
sqrt((y^2 + x^2) / y^2) * dx =>
sqrt((x^2 + 2 - x^2) / (2 - x^2)) * dx =>
sqrt(2 / (2 - x^2)) * dx =>
sqrt(2) * dx / sqrt(2 - x^2)
x = sqrt(2) * sin(t)
dx = sqrt(2) * cos(t) * dt
sqrt(2) * sqrt(2) * cos(t) * dt / sqrt(2 - 2sin(t)^2) =>
2 * cos(t) * dt / sqrt(2 * (1 - sin(t)^2)) =>
2 * cos(t) * dt / sqrt(2 * cos(t)^2)) =>
2 * cos(t) * dt / (sqrt(2) * cos(t)) =>
sqrt(2) * dt
Integrate
sqrt(2) * t + C
Solve for t
x = sqrt(2) * sin(t)
x / sqrt(2) = sin(t)
t = arcsin(x / sqrt(2))
sqrt(2) * arcsin(x / sqrt(2)) + C
From 0 to 1
sqrt(2) * arcsin(1 / sqrt(2)) - sqrt(2) * arcsin(0 / sqrt(2)) =>
sqrt(2) * arcsin(sqrt(2)/2) - sqrt(2) * arcsin(0) =>
sqrt(2) * (pi/4) - sqrt(2) * 0 =>
(sqrt(2)/4) * pi
Use The Arc Length Formula
dy/dx = -x/(2 - x^2)^(1/2).
So, √[1 + (dy/dx)^2]
= √[1 + x^2/(2 - x^2)]
= √[((2 - x^2) + x^2)/(2 - x^2)]
= √2 / √(2 - x^2).
Hence, the arc length equals
∫(x = 0 to 1) √2 dx / √(2 - x^2)
= √2 arcsin(x/√2) {for x = 0 to 1}
= π√2 / 4.
Double check:
Note that the arc (with radius √2) is between 0 and 45 degrees (that is 1/8-th of the full circle).
So, the length equals (1/8) 2π * √2 = π√2 / 4.
I hope this helps!
y = √(2 - x^2)
dy/dx = - x /√(2 - x^2)
(dy/dx)^2 = x^2 /(2 - x^2)
1 + (dy/dx)^2 = ( 2 - x^2 + x^2) / (2 - x^2) = 2 / (2 - x^2) = 1 / (1 - (x^2/2))
SQRT [ 1 + (dy/dx)^2 ] = 1 /√( 1 - (x/√2)^2 )
arc length. s = ∫ dx /√( 1 - (x/√2)^2 ) from 0 to 1
let x/√2 = sin(t) when x = 0, t = 0 and when x = 1, t = π/4
dx = √2 cos(t) dt
s = ∫√2 cos(t) dt /√( 1 - sin^2(t) ) from 0 to π/4
= ∫√2 dt from 0 to π/4
= √2 t from 0 to π/4
= √2π/4
The given curve is y = √(2 - x^2)
=> y^2 = 2 - x^2
=> x^2 + y^2 = 2
This is eqn of circle with radius √2
we are looking circumference of 1/8 of circle ( 0 to 2π is full circle and 0 to π/4 is 1/8 circle)
C = 1/8(2π√2) = 1/4(√2π)
i'm specific that each females has their determination yet anatomically the exhilaration centres of a girl are in general placed interior in basic terms 2 inches of the front and subsequently technique beats length everythime.