# (help me in this two questions )

1. Oct 28, 2009

### r-soy

hi all

(help me in this two questions )

I put two questions with ansewr and i want the solve of it ?

ansewr questions 1

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questions 2

2. Oct 28, 2009

### r-soy

3. Oct 28, 2009

### Staff: Mentor

Your attachments are appending approval, and they might not be approved for quite a few hours. You are more likely to get some help sooner if you enter the problem directly in the forum textbox.

4. Oct 28, 2009

### r-soy

I want check my answer and in question one how i can comput the answer to 3 significant or 4 also in question 2 are this graph correct

help me

5. Oct 29, 2009

### r-soy

I want check my answer and in question one how i can comput the answer to 3 significant or 4 also in question 2 are this graph correct

help me

6. Oct 29, 2009

### HallsofIvy

Staff Emeritus
Unfortunately you cut off the part of the problem that gives the coefficient of t. Are you using the "," to separate whole and decimal parts (European notation) or to separate thousands (American notation). In other words is that coefficient "one and three hundred eighty six thousandths" or is it "one thousand three hundred eighty six"?

If it is the latter, you are way off. Do the whole problem again. If it is the former, you have misplaced the comma in the answer. As for writing it to "three significant figures" what do you understand "significant figures" to mean?

I don't understand your question in (2). "How can I know in (some symbol) demand N or N0". I might guess that "N" means "natural numbers" (positive integers). Does "N0" mean "whole numbers" (non-negative integers).

If you are asking whether the domain is intended to be all positive integers or all non-negative integers, the answer is "neither"! The default domain for an exponential function is all real numbers- both positive and negative, and fractions, etc.

I would recommend using at least two or three negative numbers, as well as 0 and three or four positive values. (For t= 5 you seem to have confused "," and "." again.)

7. Oct 29, 2009

### Staff: Mentor

Your graph is nowhere close to what it should be. You have calculated some value that satisfy N = e1.386t, but the three points you plot are on a straight line, and two of y values you plotted don't agree with the values you calculated. The graph of N = e1.386t is NOT a straight line.