check my math correct or not.

[ishagal1818]

can any one assist to check my below solution correct or not?

Differentiate each of the following with respect to x:
Question A. f(x) = 3x^2 .( x^2- 2x)
Answer: =3x^4-6x^3
=(3*4x^4-1)-(6*3x^3-1)
=12x^3-18x^2

Question B. g(x) = (1/3)x^3 - 2x -7
Answer: =(1/3)*[3x^3-1]-2*1x^1-1 - 0
=3x^2 - 2x^0
3x^2-2

Question C. h(x) =1 / x^2 - 2√x
Answer: = (x^-2) -2x^½
= (-2x^-2-1) - [(-2)(1/2)x^½-1
= -2x^-3 + x^-½



Given the function f(x) = e(2 - x) + 1

Question A. Identify the domain and the range of the function.

Answer:

Domain : -∞, ∞

Range: 1 , ∞

Explanation for the range: Since e is greater than 1, the bigger the power “(2-x)” gets, the greater the output will be - this grows without bounds. The smaller (the more negative) the power gets, the closer e(2-x) gets to 0 and then you add 1.



Question B. Find lim f(x) when x → ± ∞

Answer: =e^(2-±∞) +1

For x -> ∞, f(x) -> 1

For x -> -∞, f(x) -> ∞



Question C. Identify the asymptote to the function graph.

Answer: It will have asymptote at y=1


Question D. Find the value of f(x) when x = 0 and when x = 2.

Answer: When x = 0

=e^(2-0) + 1

=e^2 + 1

put value of e = 2.718

= (2.718)^2 + 1

= 7.389 + 1

= 8.389



Now when x= 2

= e^(2-2) + 1

=e^0 + 1

= 1 + 1

= 2

 

[anon_hedgepig]

Some advice to you, pick up some tools like wolfram alpha, or if you want to get serious, mathematica/matlab (some computer algebra system). They can answer all your questions - wolfram alpha queries are free.

also you posted a calc question in the entirely wrong section...

 

[Steven G]

can any one assist to check my below solution correct or not?

Differentiate each of the following with respect to x:
Question A. f(x) = 3x^2 .( x^2- 2x)
Answer: =3x^4-6x^3
=(3*4x^4-1)-(6*3x^3-1)
=12x^3-18x^2
f(x) = 3x^4-6x^3 = 12x^3-18x^2 = f'(x)
What you wrote above is not correct! We name functions to make them different from one another. While f'(x) = 12x^3-18x^2 it does not equal 3x^4-6x^3 as you wrote!
Question B. g(x) = (1/3)x^3 - 2x -7
Answer: =(1/3)*[3x^3-1]-2*1x^1-1 - 0
=3x^2 - 2x^0
3x^2-2
(1/3)*3 is not 3
Question C. h(x) =1 / x^2 - 2√x
Answer: = (x^-2) -2x^½
= (-2x^-2-1) - [(-2)(1/2)x^½-1
= -2x^-3 + x^-½
Again do not write that (x^-2) -2x^½ = (-2x^-2-1) - [(-2)(1/2)x^½-1 as it is not true!


Given the function f(x) = e(2 - x) + 1 I suspect that you meant to write e^(2 - x) + 1

Question A. Identify the domain and the range of the function.

Answer:

Domain : -∞, ∞

Range: 1 , ∞

Explanation for the range: Since e is greater than 1, the bigger the power “(2-x)” gets, the greater the output will be - this grows without bounds. The smaller (the more negative) the power gets, the closer e(2-x) gets to 0 and then you add 1.



Question B. Find lim f(x) when x → ± ∞

Answer: =e^(2-±∞) +1 What does that even mean?

For x -> ∞, f(x) -> 1

For x -> -∞, f(x) -> ∞



Question C. Identify the asymptote to the function graph.

Answer: It will have asymptote at y=1


Question D. Find the value of f(x) when x = 0 and when x = 2.

Answer: When x = 0

=e^(2-0) + 1

=e^2 + 1

put value of e = 2.718 Why are you computing f(2.718)? You were only asked to compute f(e) and f(2).

= (2.718)^2 + 1

= 7.389 + 1

= 8.389



Now when x= 2

= e^(2-2) + 1

=e^0 + 1

= 1 + 1

= 2

My responses are in red above.

 

[ishagal1818]

My responses are in red above.

thanks but can you tell me that will be result of Answer: =3x^4-6x^3 ?

 

[Steven G]

thanks but can you tell me that will be result of Answer: =3x^4-6x^3 ?

I told you the answer above.
What you wrote above is not correct! We name functions to make them different from one another. While f'(x) = 12x^3-18x^2 it does not equal 3x^4-6x^3 as you wrote!

 

[ishagal1818]

I told you the answer above.
What you wrote above is not correct! We name functions to make them different from one another. While f'(x) = 12x^3-18x^2 it does not equal 3x^4-6x^3 as you wrote!

do you know the correct answer? or i have to send you money to get correct answer?

 

[Steven G]

do you know the correct answer? or i have to send you money to get correct answer?

You can send me money if you like. Do you know what you want to find out out? What is it called? Might I have shown you the answer in my last post? I think so?

 

[Otis]

do you know the correct answer? …

Hi ishagal. Your expression for the derivative is correct. Jomo has pointed out that your work doesn't use equal signs properly and that we ought to use function notation for derivatives, in calculus class.

You wrote:

Answer: =3x^4-6x^3

That's not the answer.

When a person writes something like

Answer = a
= b
= c

it means that a, b, and c are all equal to one another and so each line shows an answer.

The following makes sense.

f(x) = 3x^4 - 6x^3

(3*4x^[4-1])-(6*3x^[3-1])

Answer = 12x^3 - 18x^2

By the way, please note the grouping symbols shown in red. When we type an exponent containing more than a single number or symbol, we must enclose it within grouping symbols. (Remember "Order of Operations".) Later, you might be using software in math, and computers need those grouping symbols in order to recognize what's in the exponent position and what's not.

The other point Jomo made is that "Answer" means "First derivative of function f with respect to x". We have a useful function notation (symbol) for that.

f'(x) = 12x^3 - 18x^2

?