3x + 2y = 10 .....multiply by -2
2x + 3y = 15/2...multiply by 3
------------------
-6x - 4y = -20 (result of multiplying by -2)
6x + 9y = 22.5 (result of multiplying by 3)
-----------------add
5y = 2.5
y = 2.5/5
y = 1/2
3x + 2y = 10
3x + 2(1/2) = 10
3x + 1 = 10
3x = 10 - 1
3x = 9
x = 9/3
x = 3
solution is (3,-1/2)
Answer:
the perimeter of rectangle is 52cm if two adjacent sides are (2×+3)cm and (×+5)cm
The equation of the tangent line at x=1 can be written in point-slope form as
... L(x) = f'(1)(x -1) +f(1)
The derivative is ...
... f'(x) = 4x^3 +4x
so the slope of the tangent line is f'(1) = 4+4 = 8.
The value of the function at x=1 is
... f(1) = 1^4 +2·1^2 = 3
So, your linearization is ...
... L(x) = 8(x -1) +3
or
... L(x) = 8x -5
To find where the second derivative of the function changes sign, from negative to positive, or vice-versa. So, we find the second derivative of the given function.