Grade 11 U Math help NAO PLOX.

[Abel37]

It still makes no sense :/ like why only do -456^4? What about the 7? And how did you get 1/7? And how come when I do -43237380096 x 1/7 it gives me a HUGE number, like 6885734743 or something?

1^(4/7) is the same as this (1^(4/1))^(1/7)

You're getting that huge number as you're multiplying it by (1/7) instead of raising it ( ^ ) by (1/7). Remember when you're raising a number by a fraction be sure to put the fraction in parentheses.

Here is a screen of my calculator showing that (4/7) = (4/1)*(1/7):

Here is a screen of my calculator showing the differences of multiplication and raising a number with an exponent:

 

[pkingworrier]

ah, I see.

 

[Niini]

1) What restrictions are there on the value of x ^ -1/2? Are these restrictions different for x ^ 1/2? Explain.

X cannot be zero or a negative, else you would have a negative root or zero on the denominator. The difference between the two is that x ^-1/2 can't be zero but the other can. Therefore the y value cannot be negative either.

This means the restrictions are x>0 and y>0

 

[Niini]

a) -456^4/7

-33.068

b) 98^0.75

31.147

c)(5/8)^5/8

0.745

d) (^5√-1000^3)

You've butchered this. Seeing as you have no clue about a-c im presuming you havn't done imaginary numbers yet so i'll presume the question should say
5√(1000^3)

Which would equal 63.096

If you do infact have managed to learn imaginary numbers the answer of 5√(-1000^3) would be 50000.i.(10)^1/2

 

[Abel37]

d) (^5√-1000^3)

You've butchered this. Seeing as you have no clue about a-c im presuming you havn't done imaginary numbers yet so i'll presume the question should say
5√(1000^3)

Which would equal 63.096

If you do infact have managed to learn imaginary numbers the answer of 5√(-1000^3) would be 50000.i.(10)^1/2

You're incorrect. If the root of the number is odd there will not be any imaginary numbers. Here is an example: ³√27 = -3. Do you see how it does not equal 3i?

Even if you did this on a calculator you would not get any imaginary number:

 

[Niini]

No, I'm talking about 5 x √(-1000^3), settle down, and incase he wasn't I gave him the number you came up with anyway. I inluced y and x =/= 0 in the text but forgot in my final answer.

Your second part is an error common to most calculators when you enter the answers using the power function instead of the root button, unless your into imaginary numbers you cannot have a negative inside the root, unless as you said before its odd. Your answer of -0.5 is not correct as you cannot get it from letting -0.5 = 1/√x
-0.5 = 1/√x
-0.5 . √x = 1
√x = -2
Square both sides
x = 4 (which is not -4)

The graph of y = 1/√x is

read the limits off it however you want

 

[Abel37]

No, I'm talking about 5 x √(-1000^3), settle down, and incase he wasn't I gave him the number you came up with anyway.

If you subbed in x = -4 you would get y = -4^(-1/2) which is 1/(√-4) which does not equal -0.5 at all. I inluced y and x =/= 0 in the text but forgot in my final answer.

I got mixed up with the "X = -4" problem. I accidentally forgot the parentheses making the equation -(1/√4) equaling -.5

As for the 5 x √(-1000^3) I don't see what is wrong.
-1000^3 = -1,000,000,000

5 x √-1,000,000,000 = -63.09573445

-63.09573445^5 = -1,000,000,000

Did I make a mistake?

 

[Niini]

I got mixed up with the "X = -4" problem. I accidentally forgot the parentheses making the equation -(1/√4) equaling -.5

xD gotta hate them

As for the 5 x √(-1000^3) I don't see what is wrong.
-1000^3 = -1,000,000,000

5 x √-1,000,000,000 = -63.09573445

-63.09573445^5 = -1,000,000,000

Did I make a mistake?

Yes but it was in understanding my post, I'm talking about 5 times (-1 000 000 000)^1/2 not (-1 000 000 000) ^ 1/5

Read my earlier post again, didn't mean to post it so I edited all my stuff in.

 

[Abel37]

xD gotta hate them



Yes but it was in understanding my post, I'm talking about 5 times (-1 000 000 000)^1/2 not (-1 000 000 000) ^ 1/5

Read my earlier post again, didn't mean to post it so I edited all my stuff in.

Oh, okay! Well, at least opening poster got the help that he needed.