Casio FX991ES Scientific Calculator - Answered Questions & Fixed issues

Follow these: 1. Turn off your calculator(Shift+AC) 2. Click ON 3. Click "Shift+AC+MODE" 4. Hurrah! Thank me! Or, 1.Shift+7+ON This will open diagnostic mode, here you can reset your FX 991EX.

MOD simply calculates the remainder that is left over after dividing by the MOD parameter.For example, 10MOD7 = 3 since you can only divide 7 into 10 once, leaving a remainder of 3.For larger numbers, eg 389487MOD31 you start by dividing 389487 by 31, which gives 12564.09677 (on the display), however you only want the fractional part so subtract 12564 to give 0.0967741935 . This includes the lower value digits that were previously hidden. Then multiply this result by 31 which gives 2.999999999 on the display. Since the result of a MOD calculation has to be a whole number, the answer needs to be rounded to 3. If the answer doesn't easily round to a whole number, it is likely that you have gone beyond the calculators working capacity.An alternative method is to take the integer part of the first result (12564) and multiply it by 31 to get 389484, then subtract this from 389487, giving the answer of 3.

Hi, You did not put the batteries in correctly. Please replace in correct + to + and - to -....This should fix this issue.

See captured images below

Turn calculator on. Press SHIFT Mode Scroll Down to go to next page Press 8, then use left arrow to dim or right arrow to darken the screen. See the screen capture below (these are for the FX82ESPlus) For your calculator, it will be 8 CONT

If the quadratic equation has no roots, you cannot find the roots. The discriminate is negative, so if we attempt to use the quadratic equation, we get no roots. For example, y=x^2 +0x + 3 a=1, b=0, c=3 (-b+/- sqrt(b^2 -4ac))/2a Substituting in the numbers, we get x= (-0 +/-sqrt(0^2 - 4(1)3))/2 x= (0 +/- sqrt (-12))/2 We cannot do the square root of -12. Therefore, there are no roots. This is the same as having no x-intercepts. The discriminant is b^2-4ac. In this case it is -12. Thus, there are no real roots. However, you can still determine the maximum or minimum, the vertex, the axis of symmetry, the y-intercept and the stretch/compression. With this information you can graph the equation. In this case, the y-intercept is 3, the vertex is at (0,3), the axis of symmetry is x=0, the minimum value of the function is 3. Good luck. Let me know if you have any questions. Paul

Guys please tell me how can i truncate the entire fractional part (Explicit integer Type conversion) in my fx991 es calculator?it helps me a lot in solving my cryptography problems easily...

The calculator may have been subjected to a hacking procedure found on the Internet. Find a way to undo the hack or buy another calculator. Or hold it upside down to read the display (once you get the last result.)

The calculator was probably subjected to a hacking procedure. Buy another one.

No a bad idea.

Use nPr, which is the shifted function of the multiply key. For example, to find the number of permutations of six items taken three at a time, press 6 SHIFT nPr 3 =

Use nCr (the shifted function of the divide key). For example, to find the number of combinations of five things taken three at a time, press 5 SHIFT nCr 3 = and see 10.

Set Input/output to MathIO. Press the Integrate key, to the right of CALC. The image of integral appears with a rectangle for the function, and two small squares (one for the upper limit the other for the lower limit). Type in the integrand (the expression you want to integrate) in the bigger (on your display) rectangle. Use appropriate parenthesis. To type in X press [ALPHA] ) Use the down arrow to move cursor to the square for the lower limit. Type in the lower limit. Use the Up arrow to move cursor to the upper limit square. enter the upper limit. Press [=] key. If you did not make mistakes, and your expression is not too complicated you should get your integral. Note: The screen captures are not from a Casio FX991ES. But that should not matter to you.

Given the cost of the calculator, it probably will be much cheaper to just replace the calculator rather than paying for and installing a new screen.

You can use the setup to set the angle unit to be degree. Press [SHIFT][MODE](Setup) >3:Deg .See Screen capture. Alternatively you can enter the unit (degree) in the function. Press [SHIFT][ANS] (DRG>] and select the degree unit). See screen capture You get the same result as above. Note the degree symbols inside the function.

Try a reset SHIFT 9 (CLR) and reset 3:All Also if Mode:1: COMP gives Complex, maybe MODE:2:CMPLX will give you the usual COMP mode. (wires may be crossed). I have a calculator that has two keys inverted. I made a note of it and keep it taped inside the sliding cover.

There is nothing to convert, because if T is a real number so is 40sin(4000T). 40sin(4000T)=40abs(sin(4000T))*sign(sin(4000T)) where abs() is the absolute value of it argument, and sign(sin(4000T)) is positive or negative. So in (radius, angle) polar coordinates r= 40 abs(sin(4000T)), theta =(0, or PI), depending on sign(sin(4000T)) If you are trying to graph parametric functions, this calculator does not do graphs, and you need another function of T

Ah! that perennial desire for eternity. The calculator uses solar power. It also have a battery. Under normal circumstances you won't need a battery, may be if you are living through a long Nuclear Winter. Any way, just get a battery with the same characteristics as the one that shipped with the calculator: voltage, thickness, diameter. That is what counts.

Read the Appendix of the manual. It contains examples of each type of calculations. Put calculator in STAT Mode, select 1-var stat, enter the data and get the mean as x_bar In the manual see the examples 052, 053 054, ... on pages 16, 17 and following.

Sorry, I have no idea how to solve your problem but I sure would like to see an image of this oddity. Thanks.