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Tukutuku. Adapted from Peter Hughes. Tukutuku panels are made from crossed weaving patterns. Here is a sequence of the first four triangular or tapatoru (tapa = side, toru = three) numbers. Another set has been rotated 180 degrees and added as shown below.
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Tukutuku Adapted from Peter Hughes
Tukutuku panels are made from crossed weaving patterns. Here is a sequence of the first four triangular or tapatoru (tapa = side, toru = three) numbers.
Another set has been rotated 180 degrees and added as shown below. Build these from tapatoru the pieces.
T100 = 100 x 101 2 = 5050 How do you find the 100th triangular number? Generalise: Find a formula for the nth triangular number Tn. Tn = 101 100
Tapawha Numbers Let S4 stand for the 4th square or tapawha (tapa = side, wha = four) number. Create S4 from tapatoru pieces. S4 = T4 + T3 Generalise: Link Snto the tapatoru numbers. Sn= Tn + Tn-1
Algebra Skills Show Sn= Tn+Tn-1 by algebra. Tn+Tn-1 = n(n+1) + n(n-1) 2 2 = n(n+1)+n(n-1) 2 = n(n+1+ n-1) 2 = n2+n+n2-n 2 = 2n2 2 = n2
Patiki Patterns Look at the fourth Patiki (flounder) pattern. Why is it called the fourth one?
Write a formula for P4, the 4th Patiki number, in terms of the tapatoru numbers. P4 = T4 + 2T3 +T2 Generalise: Find a formula for Pn Pn= Tn+ 2Tn-1 +Tn-2
Algebra Skills Find a formula for Pn Pn= Tn+ 2Tn-1 +Tn-2 = n(n+1) + 2 x n(n-1) + (n-2)(n-1) 2 2 2 = n(n+1) + 2n(n-1) + (n-2)(n-1) 2 = n2 + n + 2n2 - 2n + n2 - 3n + 2 2 = 4n2 - 4n + 2 2 = 2n2 - 2n + 1
Patiki via Tapawha Look at the fourth Patiki pattern This shows P4 = S4 + S3 = +
Algebra Skills Find a formula for Pn Pn= Sn+ Sn-1 = n2 + (n-1)2 = n2 + n2 - 2n + 1 = 2n2 - 2n + 1
Patiki via Tapawha again Look at P4 and link to tapatoru numbers P4 = 4T2 + number of crosses in the middle
Algebra Skills Find a formula for Pn Pn= 4Tn-2+ 4n-3 = 4 x (n-2)(n-1) + 4n-3 2 = 2(n-2)(n-1) + 4n-3 = 2n2 - 6n + 4 + 4n - 3 = 2n2 - 2n + 1
Patiki via Rotation P4 is shown below and rotated Rotating helps recognise in the fourth pattern there are 4 diagonal lines of 4 white rectangles, and 3 diagonal lines of 3 darker rectangles. So there are 4 x 4 + 3 x 3 = 25 rectangles altogether. = Rotate 45º
Algebra Skills Find a formula for Pn Pn= n2 + (n – 1)2 = 2n2 - 2n + 1 Again!
Patiki via Both Tapatoru and Tapawha Discuss why P4 = S7 – 4Tn-1
Algebra Skills Find a formula for Pn Pn= S2n-1 – 4Tn-1 = (2n-1)2 – 4 x (n-1)n 2 = (2n-1)2 - 2(n-1)n = 4n2 - 4n + 1 - 2n2 – 2n = 2n2 - 2n + 1