Teaching trig on the xy plane and “All Students Take Calculus” came up. I’m ready for a new phrase. I’ll have a contest with my students to create their own phrases.

Any ideas?

#iteachmath
#edusky
#MtBoS
#trigonometry

My students love Cramer’s rule. They like to look back on all their algebra work and see how this approach solves all 2x2 systems from previous classes. The fact that it works beyond is something of a bonus for us. Here is our justification for it:

(2/2) I use the fact that (x - (a - bi))(x - (a+ bi)) = x^2 -2ax + (a^2 +b^2) and I like this because it emphasizes the sum of squares. Your student's approach simplifies to the same short cut and I love it! Way to go!!!

(2/2) Seeing students apply their ideas to algorithms is still one of the best aspects of teaching. Here is the student algorithm that I was able to share back with the class today. Sometimes long division is a better choice than synthetic division! Also, these topics rule.

#MathSky #iTeachMath

(1/2) Aren't students amazing? I showed how to use synthetic division to factor a polynomial. The first question I get is about how to avoid synthetic division and use long division! Then I realized I had a similar question three years ago! Here is the original approach:

#MathSky #iTeachMath

Anyone else getting ads like this?

By the way…I like when kids ask “when will we use this?” It is a great conversation starter!!

#iteachmath #mtbos

Votes updated!

#ITeachMath

Took a little poll in class today. So far only 1 student is all in for Tau.

Where do you stand?

#ITeachMath #MathSky #EduSky

Proved the sine and cosine sum formulas today! #Mtbos #iTeachMath

Proving the angle sum and difference with sine and cosine tomorrow and just found this gem on Trigonography.
trigonography.com?p=70

I haven't seen it before and prefer it to some other proofs I have used.

Has anyone else used this? Do you have any that you prefer? #mtbos #iTeachMath