Wednesday

March 4, 2015

March 4, 2015

Posted by **help please.** on Sunday, March 11, 2012 at 12:03pm.

a- if f is a function of x and y and a is a real number, then f(ax, ay)= af(x,y).

b- if fx(a,b) < 0, then f is decreasing with respect to x near (a,b).

- calculus -
**Steve**, Sunday, March 11, 2012 at 1:35pm(a) is certainly not true in general. While it is true for linear functions, it is otherwise not true.

f(x,y) = x^2/(y^2+1)

f(ax,ay) = (a^2x^2)/(a^y^2+1)

or

f(x,y) = sin(x+y)

f(ax,ay) = sin a(x+y)

or

f(x,y) = e^x * ln(y)

f(ax,ay) = a^ax * ln(ay) = e^a * e^x * (lna + lny)

(b) I assume fx means the partial with respects to x. That's true. The derivative is the slope of the curve in the intersection of f(x,y) and the plane y=b.

**Answer this Question**

**Related Questions**

calculus - determine whether the statement is true or false. If it is true, ...

math - Algebra For questions 1-5, find the value of the variable. 1. x = (1 ...

7th grade health true or false - 11. Disagreements are a normal part of life. (1...

7th grade health Ms. Sue please thanks - True/False Indicate whether the ...

Math - Determine whether the statement is true, false, or sometimes true. ...

Physical Ed - 11. Disagreements are a normal part of life. (1 point) True False ...

math - Indicate whether each statement is true or false by checking the ...

math - Indicate whether each statement is true or false by checking the ...

math - Indicate whether each statement is true or false by checking the ...

Math - Explain which method you would use to determine whether the following ...