TI-84 Battery Leak (How to repair your TI-84 Plus Pocket SE)

Today I had a bad shock when my trusted TI-84 Plus Pocket SE Calculator could not be turned on. I just purchased it last year, and TI-84 Calculators are not exactly cheap as every JC student in Singapore would know.

On Amazon, the Texas Instruments TI-84 Plus Silver Edition Graphing Calculator, Silver sells for a whopping $174.99, which is almost like half the price of a smart phone. Students in Singapore can buy it at a slightly lower Student Price, but however as I am no longer a student, I would probably need to pay the full price, unless I get one of my cousins to  help me buy one.

How to Repair the TI-84 (Cannot even switch on)

First, I did the common sense approach of changing all the AAA and even the button LR44 battery. No luck…

ti-84 battery leak
TI-84 Battery Leak

I noticed something strange happened to one of the batteries. A layer of yellow crust has coated the battery case. (I was using Ikea batteries)

I followed the 5 steps I found on the TI-84 troubleshooting site:

  1. Try a new set of AAA batteries.
  2. Adjust the contrast by pressing and releasing [2ND] followed by pressing and releasing [▲]; repeat as necessary. To adjust or lighten the display, use the down arrow.
  3. Remove one of the AAA batteries. Press and hold [CLEAR]. While holding [CLEAR], reinsert the AAA battery and press [ON]. The calculator should display the message “RAM Cleared“. Release [CLEAR] and then press it one more time to remove the message.
  4. Remove one of the AAA batteries. Press and hold [DEL]. While holding [DEL], reinsert the AAA battery and then press [ON]. The calculator should display “Waiting…Please install calculator software now“. Follow the instructions for the TI-83 family or TI-84 Plus family to reinstall the calculator operating system.
  5. Remove all of the batteries including the round lithium battery for 5 minutes. After the 5 minute period, reinsert all of the batteries and turn the calculator on. Adjust the contrast if necessary.

After trying all the 5 steps, I still couldn’t get the TI-84 to switch on.

I then used a piece of tissue to wipe of the battery contacts which were coated with the battery leak. Then, I tried step 5 again.

Thank God, the TI-84 sprung back to life again, and I can save $200 for now…

H2 Math Condensed Notes

For those taking H2 Maths, do check out my H2 Maths Condensed Notes with Bundled Prelim Papers!

ti-84 repaired
TI-84 back to life

What is the Difference between H1 Mathematics, H2 Mathematics and H3 Mathematics?

Source: http://www.temasekjc.moe.edu.sg/what-we-do/academic/mathematics-department

Note: Additional Mathematics is very helpful to take H2 Mathematics in JC!


There are three mathematics syllabi, namely H1 Mathematics, H2 Mathematics and H3 Mathematics.

Students who offered Additional Mathematics and passed the subject at the GCE ‘O’ level examination may take up H2 Mathematics. Students posted to the Arts stream and did not offer Additional Mathematics at the GCE ‘O’ level examination are not allowed to take H2 Mathematics but may consider taking up H1 Mathematics. However, students who are posted to the Science stream but did not offer Additional Mathematics at the GCE ‘O’ level examination are advised to offer H2 Mathematics if they intend to pursue Science or Engineering courses at a university. Students who wish to offer H3 Mathematics must offer H2 Mathematics as well.

The use of a Graphing Calculator (GC) without a computer algebra system is expected for these Mathematics syllabi. The examination papers will be set with the assumption that candidates will have access to GCs.

H1 Mathematics

H1 Mathematics provides a foundation in mathematics for students who intend to enrol in university courses such as business, economics and social sciences. The topics covered include Graphs, Calculus and Statistics. A major focus of the syllabus would be the understanding and application of basic concepts and techniques of statistics. This would equip students with the skills to analyse and interpret data, and to make informed decisions.

H2 Mathematics

H2 Mathematics prepares students adequately for university courses including mathematics, physics and engineering, where more mathematics content is required. The topics covered are Functions and Graphs, Sequences and Series, Vectors, Complex Numbers, Calculus, Permutations and Combinations, Probability, Probability Distributions, Sampling, Hypothesis Testing, and Correlation and Regression. Students would learn to analyse, formulate and solve different kinds of problems. They would also learn to work with data and perform statistical analysis.

H3 Mathematics

H3 Mathematics offers students who have a strong aptitude for and are passionate about mathematics a chance to further develop their mathematical modeling and reasoning skills. Opportunities abound for students to explore various theorems, and to read and write mathematical proofs. Students would learn the process of mathematical modeling for real-world problems, which involves making informed assumptions, validation and prediction. Students may choose from the three H3 Mathematics modules, namely the MOE-UCLES module, the NTU Numbers and Matrices module and the NUS Linear Algebra module.

The MOE-UCLES module is conducted by tutors from our Mathematics Department. The three main topics to be investigated are Graph Theory, Combinatorics and Differential Equations. This module would be mounted only if there’s demand.

The NTU Numbers and Matrices module is conducted by lecturers from the Nanyang Technological University (NTU). Students would have to travel to Hwa Chong Institution to attend this module.

The NUS Linear Algebra module is conducted by lecturers at the National University of Singapore (NUS). Students who offer this module would have to attend lessons together with the undergraduates at the university.

How to use tables in CASIO FX-9860G Slim (H2 Maths Tuition)

Tables in CASIO FX-9860G Slim

The most popular Graphical Calculator for H2 Maths is currently the TI-84 PLUS series, but some students do use Casio Graphical Calculators.

The manual for CASIO FX-9860G Slim is can be found here:


The information about Tables and how to generate a table is on page 121.

Generating tables is useful to solve some questions in sequences and series, and also probability. It makes guess and check questions much faster to solve.

h2 tuition gc
Picture of the CASIO FX-9860G Slim Calculator