What do the plus and minus numbers mean on eye prescriptions? I have a minus 2 number in one eye and minus 2.5 in the other and I have no idea what that means.

Fixya maths 4 indices

Indices n surds

Hai again your support helps me alot can you please differentiate for me between the following -6to the power 2 and -6 to the power 2,& 2 to the power -3 + 1/3 to the power-2
I need a clarity how to convert these exponents to fractions
Posted by Ncwana Noziphiwo on Apr 03, 2018

https://www.tes.com/teaching-resource/indices-negative-indices-6427219

-62 means a number multiplied by itself twice
So in this case it is -6 x -6 = 36 - since -x- = +
If this was -6-2 the negative power means it's a fractional indice so first make it look like a fraction
1/-62 now it looks like a fraction (inverse) and the power mow looks like a normal square
Coz its still a negative number -6 x -6 = 36
So the answer is now 1/36

So when it is a minus power, first turn it into a fraction, then calculate as normal
Note: every number has a sign, it is either + or minus.
By convention, we always assume it is a plus unless stated otherwise.
To make sure u remember this fact put a plus sign in front of every number if no sign is showing
You can start with buses the 27 bus is +27
Its like if u say u have a car, what u really mean is you have 1 car. But u drop the 1 coz everyone takes for granted u meant 1 car, 1 house, 1 friend etc
Every power we assume its + unless otherwise stated.
So when a minus is put in front of the power, its saying make it a fraction first!
Maths is a game and games have rules.
This rule is a minus in front of power (indice) change to fraction form first!
So if it is 2-3 - the power -3 is saying turn it into a fraction first so
1/23 = 1/ 2x2x2 = 1/8
If it had of been 23 notice how no signs shown because we take for granted they r all +
Let's show them
+2+3 since it's a plus 3 we don't need to change it to a fraction and since it is a plus 2
We have +2 x + 2 x +2 and a +x+ x+ = +
2x2x2 = 8
Its easier to just do 23 = multiply the 2 by itself 3 times
2x2x2 = 8
When doing fractions of any type I prefer showing them as being more obviously top/bottom
1
-
2

Format and for that free hand is easier as typing is hard...lol
Ie
Numerator Denominator
When using a number that's a fraction it is better tro enclose it in brackets
As every indice is of the form - numberpower
The number can just as easily be a fractional number like a 1/3
So (1/3)2 is a third multiplied by itself
1/3 x 1/3 = 1x1/3x3 = 1/9
If it was (1/3)-2 then first u must get rid of the minus power by turning it into a fraction
1/(1/3)2
1/1/3 x 1/3
1/1/9
And 1 divided by a ninth =
1 to be cont - tired..lol

Minus and change-sign are two completely different things. Minus is used to subtract one number from another. When you press minus when the input line is empty, your telling the calculator to subtract. The only way it can subtract the number you're about to put in is to subtract it from something else, and that something else is the previous answer, hence the "Ans."

If you want to input a negative number, use the change-sign key. If you want to subtract one number from another number, use the minus key.

Try pressing the plus key when the input line is empty. You'll get Ans+ in this case as well, The same with multiply and divide, among others, and for the same reason.

It means "six point one times ten to the minus four" or 0.00061 .

Read the "E" as "times ten to the". The calculator switches to scientific notation when the number is too small or too large to display using the current display mode.

Be it any kind of contact lens prescription/nonprescription a brief discussion with the eye expert is as necessary as your eyes need vision more clearly. Indeed you can go and buy the prescription contacts without consulting to doc, but to be honest that would be at your own risk (especially about your eyes).

Your question is interpreted in following way as it is not clear as cube of what & minus of what?
2x minus x cube plus 5 x minus 2

Solution 1:
= 2 x -1 x cube plus 5 x minus 2
= -2x cube plus 5 x minus 2
= cube of -2 plus 5 x minus 2
= (-8 +5) x -2
= -3 x -2
= 6

Solution2:
=2x-1x cube of +5 x -2
= -2 x 125 x -2
= 500

I think logically the solution 2 must be right. How you interpret the question is important.

sonsunny

Most of these timers have 3 buttons, the hand and the plus and minus buttons. Try pressing the minus and plus buttons at the same time. The display should flash. Then adjust the time with the plus and minus buttons. If this doesn't work just try different combinations of pressing 2 buttons. If the timer is not faulty on of these combinations will work.

Do you need help doing your homework?

If so, here's a first attempt. It may be correct, and it may not be.
It's up to you to understand the process, and to make any needed corrections.

X minus 11 equals Y.
So, X is larger than Y.
So, 3 times X minus 33 equals 3 times Y.
Thus 3 times X equals 3 times Y plus 33.
Also, 3 times X minus 4 equals 4 times Y.

So, (3 times Y plus 33) minus 4 equals 4 times Y.

Thus 0 times Y plus 29 equals 1 times Y.

So, Y equals -27.

Hello,
I am not sure what the cross (x) means: is it a multiplication or the variable x, so I took a screen capture of both cases.

The top case is obtained as follows the asterisk is the multiplication sign to thr right of digit 9; the small minus is the change sign key the minus sign in parentheses under digit 3 and to the left of ENTER key.; the forward slash is the division sign, above the multiplication sign.
This small minus called change sign makes a positive number negative and a negative number positive, hence its name. If your expression starts with a negative sign that is the one to use. Use it also for negative exponents.

As you can see the result is -.8. Notice how the - before the dot is small with respect to the regular minus, as in the last expression.

For the last expression on the screen capture, there is nothing special, except that you have two ways to enter the variable X.

1. Press [ALPHA] [STO->]
2. Press the key [X,T, Theta, n] to the right of the green [ALPHA] key.

Hope it helps.



If x is the multiplication sign
8[x] [(] (-)1

I'm assuming you want the +/- symbol like you see in the quadratic formula. There is no key to enter this. You will have to enter 2 separate problems. Enter the numbers with the + symbol and then enter the numbers with the - symbol.