Page 99 - Bangladesh_classwiz_BOOK2018_rev_Neat

D`vniYgvjv

1. (−1) +1 AbyµgwU wjL‡Z n‡e|
+1

mgvavb- cÖ_‡g K¨vjKz‡jUi‡K Table mode-G wb‡q ( ) G (−1) +1 +1 Gi Abyiƒc Abyµg

(−1) +1 cÖ‡ek Kiv‡Z n‡e| Gici , I wn‡m‡e 1, 10 I 1 wb‡j GKwU gv‡bi
+1
ZvwjKv cvIqv hv‡e|

(Key log- w9(p1)^[+1$Oa[$[+1==
1=10=1==)

( ) Gi gvb¸‡jv n‡e AbyµgwUi c`| K¨vjKz‡jUi n‡Z †`Lv hv‡”Q AbyµgwUi c`¸‡jv n‡jv
1 2 3 4 5
, − , , − , , … … … … … …
2 3 4 5 6

2. 5 + 8 + 11 + 14 + ⋯ … … … … .. avivwUi ‡Kv‡bv c` 383 Zv †ei Ki‡Z n‡e|

mgvavb- GLv‡b avivwUi cÖ_g c` = 5 Ges mvaviY AšÍi = 8 − 5 = 3 myZivs avivwUi Zg c` n‡e
5 + ( − 1) × 3. K¨vjKz‡jU‡i 5 + ( − 1) × 3 = 383 UvBc K‡i qr ( ) Pvc‡j
Gi GKwU gvb PvB‡e| Gi gvb 20 cÖ‡ek Kwi‡q = Pvc‡j wb‡Pi w¯Œ‡bi g‡Zv djvdj cÖ`wk©Z n‡e|

(Key log- w15+([p1)O3Qr383qr2
0==)

3. 7 + 12 + 17 + … … …. avivwUi 30wU c‡`i mgwó †ei Ki‡Z n‡e|

mgvavb- avivwUi mvaviY c` (5 + 2). q[ (*) ‡P‡c ′Σ′ cÖ‡ek Kiv‡bvi ci mvaviY c` wn‡m‡e
5 + 2 Ges ïiæi gvb 0 I †kl gvb 30 cÖ‡ek Kiv‡Z n‡e| Gici = Pvc‡j wb‡Pi w¯Œ‡bi g‡Zv djvdj
cÖ`wk©Z n‡e|

(Key log- q[Cq[5[+2$1$30= )

94