ElectricPavlov

Just use the division sign  (if you look ABOVE the calc display, it will appear as a fraction)

Yes, but it results in a fration, not and integer     2/5  = 0.4  

3x+5  is just that....without more info (like and equal sign and value)  , can't do more than that...

-7  *  1 3/4  =   -7  x  7/4  =  -49/4  = -12 1/4

Let's say you are on the 10:00 train  ....  you will see the train coming form the opposite direction that was launched at 6:00 after you have been traveling approx 30 minutes ...

then t you will see the 7  8  9  10  launches as you travel for  4 1/2 hours  AND you will see the 11 12 13:00 and 14:00 train launches before you arrive at the launching station at 14:30  

That is a total of  9 trains going the opposit direction as you ....

\( \frac{d}{dx}\)cos(x) = - sin(x)

= 800 - .1 x        What else do you want to do with this??

Let's find the inverse of the first one to see if it is the second one (sorry I misread this question initially)

y = (-2x-8)/3      replace x  with y and y with x

x = ( -2y-8)/3     and solve for y

3x+8 = -2y

-4 - 3/2 x = y        this IS the second function ...so they ARE inverses of each other.

2.4 x 10^-7  /  9.6 x 10^-4   =   .25 x 10^(-7- -4) = .25 x 10^-3 - 2.5 x 10^-4

sin 48 = 9/x

x = 9/sin 48 = 12.11 = hypot

Pythagor theor   to find the othe leg       9^2 + x^2 = 12.11^2       x = 8.1 cm = other leg