Ples slove 24 no. 13.
15.
16.
17.
12+32 +52 + ...+ (2n-1)2
1
1
1.4 4.7 7.10
1
1
1
1
PRINCIPLE OV MATHEMATICAL.
3
(3n+1) •
n
3.5 5.7 7.9
(2n +3) - 3(2n+3) •
18. 1 +2+3 —(2n+ 1)2.
19. n (n + 1) (n +5) is a multiple of 3.
20.
21.
24.
102n-1 + I is divisible by 11.
x2" — y2n is divisible by x + y.
32'1+2 — 8n — 9 is divisible by 8.
41 14n is a multiple of 27.
3)2.
Summary
• One key basis for mathematical thinking is deductive reasoning. I
deduction, inductive reasoning depends on working with differe
developing a conjecture by observing incidences till we have 01
