# Trigonalisation on the TI89 step by step

Trigonalisation can be done step by step on the TI89 using the LInear Algebra Made Easy at http://www.ti89.com/?a=LAME For further information and examples: https://fr.wikipedia.org/wiki/Trigonalisation#Exemples_de_trigonalisation

# Solve Cauchy Euler Differential Equation Step by Step on the TI89

2. Order Cauchy Euler Differential Equations are of the format x^2*y” + b*x*y’ + c*y=f(x) Homogeneous solutions are linear combinations of format c1*x^m1 + c2*x^m2 where m1 and m2 are zeros of a corresponding char. equation. Good news for TI89 users: This type of Differential Equation can now be solved step by step using Differential… (read more)

# Cayley Hamilton procedure on the TI89 step by step

The Cayley Hamilton is a nifty procedure to find the inverse of a matrix using the characteristic polynomial of a given square matrix. So no Row Echolon or similar is needed. We just included this Cayley Hamilton in the Linear Algebra Made Easy TI89. Best of all complete steps are shown until the inverse matrix… (read more)

# TI89.com for mobile devices

TI89.com is now mobile responsive: once you access www.TI89.com using a cell phone or tablet you will access the mobile TI89.com site. Note: the giveaway puzzle must be accessed on the full (not the mobile) site.

# New Giveaway Puzzle at www.ti89.com

Find a new Giveaway Puzzle at the top of www.TI89.com. The first person to solve this one qualifies for a free TI89 app. The solutions to the previous were clever and winners are now happy users of our TI89 apps.

# User comment (M.B.): Just want to thank you for the fabulous programs for Statistics

Stats made easy made my stats class a breeze. I got all answers correct thanks to the stats program. I love the program and will try to impress on others that the money is worth every penny when you can get an A in the class. I got a 93% in my Stats class. Thank… (read more)

# Watch John do his Calculus Homework Step by Step on the TI89

Watch John do his Calculus Homework Step by Step on the TI89: He does Limits, Derivatives, Integrals and Differential Equations in a few minutes , Step by Step Here : https://www.youtube.com/watch?v=zaguqugXlxc

# WEEKLY GIVEAWAY PUZZLE (6-11-15):

Arrange the digits 1,2,3,4,5,6,7,8,9 in order from left to right,  insert + and – as desired to get 79  ? Post solution under Leave a reply:

# Weekly Giveaway Puzzle (6-3-15)

WEEKLY GIVEAWAY PUZZLE (6-3-15): First correctly explained solution wins a FREE APP OF YOUR CHOICE!! IF WXYZ*T=ZYXW What are X,Y,W,Z,T when they are different digits ? Email us at: support@ti89.com