Help Needed with Algebra

JohnRobbo

New member
Joined
Mar 30, 2013
Messages
12
Really struggling with these questions would really appreciate some help,
answers need to be given with positive indices.

Question 1:
(0.2a^-2/3) ^3

Question 2:
3x^-3 (x-4x^2)

Queston 3:
(9x^8) ^-1/2

Thanks
 
Really struggling with these questions would really appreciate some help,
answers need to be given with positive indices.

Question 1:
(0.2a^-2/3) ^3

Question 2:
3x^-3 (x-4x^2)

Queston 3:
(9x^8) ^-1/2

Thanks
Couple of tips.
.
(1) Please show your work even if you know it is wrong. It allows us to see where you are having trouble.
.
(2) In the future, please post one question per thread.
.
(3) Give us a clue about your situation. The answer appropriate for an 8th grader studying algebra for the first time will differ from the answer appropriate for a college student taking a review course.
.
(4) When posting, be very careful to follow PEMDAS so we can be sure we understand your problem. What your first problem involves as you have written it is:
.
\(\displaystyle \left(\dfrac{2a^{-2}}{3}\right)^3.\) But I suspect you mean:
.
\(\displaystyle \left(2a^{(-2/3)}\right)^3.\)
 
Laws of exponents: \(\displaystyle a^xa^y= a^{x+ y}\) and \(\displaystyle (a^x)^y= a^{xy}\).
 
Couple of tips.
.
(1) Please show your work even if you know it is wrong. It allows us to see where you are having trouble.
.
(2) In the future, please post one question per thread.
.
(3) Give us a clue about your situation. The answer appropriate for an 8th grader studying algebra for the first time will differ from the answer appropriate for a college student taking a review course.
.
(4) When posting, be very careful to follow PEMDAS so we can be sure we understand your problem. What your first problem involves as you have written it is:
.
\(\displaystyle \left(\dfrac{2a^{-2}}{3}\right)^3.\) But I suspect you mean:
.
\(\displaystyle \left(2a^{(-2/3)}\right)^3.\)

had a go at each

Q1
1/125a^-2/27 and with positive indices = 1/125 / a^2/27.


Q2
3x^-2 - 12x^-1 and with positive indices = 3/x^2 - 12/x


Q3
1/3x^-4 and with positive indices = 1/3 / x^4

Dont know if they are correct could you help me if any are wrong
 
Really struggling with these questions would really appreciate some help,
answers need to be given with positive indices.

Question 1:
(0.2a^-2/3) ^3

Is this \(\displaystyle \left ( 0.2a^{-\frac{2}{3}}\right )^3\)

Or \(\displaystyle \left ( \dfrac{0.2a^{-2}}{3}\right )^3\)

Question 2:
3x^-3 (x-4x^2)

Queston 3:
(9x^8) ^-1/2

Thanks

.
 
\(\displaystyle \left [0.2a^{-\frac{2}{3}}\right ]^3\)

= \(\displaystyle (0.2)^3 \ * \ \left [a^{-\frac{2}{3}}\right ]^3\)

= \(\displaystyle (0.008) \ * \ \left [a^{-\frac{2}{3} \ * \ 3}\right ]\)

= \(\displaystyle (0.008) \ * \ a^{-2}\)

= \(\displaystyle \dfrac{1}{125a^2}\)
 
Last edited by a moderator:
had a go at each

Q1
1/125a^-2/27 and with positive indices = 1/125 / a^2/27.


Q2
3x^-2 - 12x^-1 and with positive indices = 3/x^2 - 12/x No one has a clue what the second question is so please repost it correctly.
Q3
1/3x^-4 and with positive indices = 1/3 / x^4 This answer is correct AS FAR AS IT GOES \(\displaystyle \dfrac{1}{3} \div x^4 = \dfrac{1}{3} * \dfrac{1}{x^4} = \dfrac{1}{3x^4}.\)

Dont know if they are correct could you help me if any are wrong
.
 
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