Let f be a function of two variables that has continuous partial derivatives and consider the points A(9, 5), B(11, 5), C(9, 7), and D(17, 11). The directional derivative of f at A in the direction of the vector AB is 5 and the directional derivative at A in the direction of AC is 12. Find the directional derivative of f at A in the direction of the vector AD. (Round your answer to two decimal places.)

Find cot x if sin x cot x csc x = √2

This is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 5 terms.

If (x + 8) is a factor of f(x), which of the following must be true? both x = –8 and x = 8 are roots of f(x). neither x = –8 nor x = 8 is a root of f(x). f(–8) = 0 f(8) = 0