I´m not sure how to explain it but I´ll give you my solution:
= 1/(c-1) - (c+1)/(1-c) (conjugates)
= (1-c)/(c-1)(1-c) - (c+1)(c-1)/(c-1)(1-c) (common denominators)
= (1-c)+(-(c-1)(c+1))/ -(c-1)(c-1) the red text is replaced with 1 due to divison
= (1+ c+1)/(c-1)
Good luck, if i have been unclear about something, ask me or someone else here:)
where B is the area of the bottom and h is the height. i assume you know how to calculate the volume. but maybe have some problems with the fractions.
for example you can do like this.
2 and 2 over 3.= 2+ (2/3) 1=(3/3) -----> 2= (6/3) ------> 2+(2/3)= (6/3)+(2/3)= 8/3
try to do the other two sides by yourself.
Then you just have to multiply the three different numbers to get the volume.
an example of that. (8/3)*(3/5)*(1/2) = 24/30 = 4/5
i hope you follow
ok, Im not totally sure about this.
a rational number is a integer number or a fraction of two integers.
an irrational number is a number that can not be written as a fraction. (pi, sqrt(2), e for example)
therefore, when you multiply an irrational number with a rational number it has to be irrational (if the rational number isn´t zero)
for example multiplie pi with 1/4 the result is pi/4 but since you can´t write pi as a fraction you can´t write pi/4 as a fraction.
you can write everything in seconds as well.
in total 5540+6270=11810sek
then you go backwars and figure out how many whole ours you got and then minutes and the seconds.
you can also switch the numbers into sexagesimal numbers but that seems a bit overkill in this case.
I´m not totally sure about this but I think it make sense :/
We can pick 3 girls out of 12 in 12*11*10 ways.
(first we can choose from 12 girls, when we picked one we got 11 to choose from and so on...)
In the same way of thinking we can pick 3 boys in 10*9*8 different ways.
then we multiplie the numbers of different ways to combine the girls with the number of different ways to combine the boys.
so we got (12*11*10)*(10*9*8)
Maybe I´m not qualified for answering your question and maybe I don´t understand english properly so don´t trust me completly
...but isn´t there just to put the numbers into the formula and use different values for t?
8 values means 8 different times. as a suggestion every half second to start with.