A company estimates that it will sell N(x) units of a product after spending $x thousand on advertising, as given by N(x)equalsnegative 0.25 x Superscript 4 Baseline plus 22 x cubed minus 472.5 x squared plus 76 comma 000, where 21 less than or equalsxless than or equal 45. When is the rate of change of sales increasing and when is it decreasing

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places

believe it or not anna is correct good job anna give me a fist bump there u go gal

570, the answer is 570, hope it