Friday

December 19, 2014

December 19, 2014

Posted by **Gabriela** on Monday, December 13, 2010 at 4:31pm.

- calculus -
**Reiny**, Monday, December 13, 2010 at 5:21pmlet the point be P(x,y)

Perimeter = 2x + 2y

= 2x + 2(x^-2)

= 2x + 2/x^2

d(perimeter)/dx = 2 -4/x^3

= 0 for min of perimeter

2 - 4/x^3 = 0

2 = 4/x^3

x^3 = 2

x = 2^(1/3) , (the cube root of 2)

y = 2^(-2/3)

(I really expected the point to be (1,1) but the Calculus shows my intuition was wrong

the perimeter with the above answers is 3.78

had it been (1,1) the perimeter would have been 4)

- calculus -
**Rob**, Sunday, April 7, 2013 at 1:14pmTry this way:

Perimeter = 2x+2

therefore P = 2x + 2/x^2

d(perimeter)/dx = (2x^3-4)/x^3

solving for x = 2^(1/3)

therefor y was given as y = x^-2

plug x into y to solve for y.

y = 2^(-2/3) or y = (1/4)^(1/3)

check the answer it should be 3.78

**Answer this Question**

**Related Questions**

Calculus - A rectangle in the first quadrant has one vertex as the origin, and ...

Calculus - A rectangle in the first quadrant has one vertex as the origin, and ...

Calculus - 3) Consider rectangles located as shown in the first quadrant and ...

calculus - Find the area of the largest rectangle with one corner at the origin...

calculus - Find the area of the region in the first quadrant enclosed by the ...

Calculus - 4. Find the area of the largest rectangle (with sides parallel to the...

calculus - Find the area and dimensions of the largest rectangle (with sides ...

Calculus - If a tangent line is drawn to the parabola y = 3 - x^2 at any point ...

calculus - If a tangent line is drawn to the parabola y = 3 - x^2 at any point ...

Calculus - I have to find the area of the largest possible rectangle that can be...