Page 102 - Bangladesh_classwiz_BOOK2018_rev_Neat

beg Aa¨vq

w·KvYwgwZ

(Trigonometry)

w·KvYwgwZ‡Z wÎfz‡Ri wZbwU evû Ges †Kv‡Yi g‡a¨ m¤úK© wb‡q Av‡jvPbv Kiv nq| w·KvYwgwZi wewfbœ †ÿ‡Î
K¨vjKz‡jU‡ii e¨vcK e¨envi i‡q‡Q| cwigvc msµvšÍ mgm¨vi mgvav‡b Ges †KvYmg~‡ni g‡a¨ m¤úK© Abyaveb
Ki‡Z K¨vjKz‡jUi mvnvh¨ K‡i _v‡K| GB Aa¨v‡q-ClassWiz K¨vjKz‡jUi e¨envi K‡i wb‡¤œv³ welq¸‡jv m¤c‡K©
Av‡jvPbv Kiv n‡e-

 ‡KvY cwigv‡ci wewfbœ GKK
 w·KvYwgwZK A‡f`vejxi mZ¨Zv hvPvB
 wewfbœ PZzf©v‡M w·KvYwgwZK AbycvZmg~‡ni wPý wbY©q

 w·KvYwgwZK AbycvZhy³ ivwki gvb wbY©q
©
 Solve dvskb e¨envi K‡i w·KvYwgwZK mgxKi‡Yi mgvavb wbYq
 wecixZ w·KvYwgwZK dvskb m¤úwK©Z mgm¨vi mgvavb
 gv‡bi ZvwjKv e¨envi K‡i †jLwPÎ A¼b I
 ¯’vbvsK e¨e¯’v m¤úwK©Z mgm¨v |

w·KvYwgwZi Calculation Kivi Rb¨ w1 †P‡c Calculate mode wbe©vPb K‡i ïiæ Ki‡Z n‡e|

9.1 ‡KvY cwigv‡ci GKK

‡KvY cwigv‡ci Rb¨ mvaviYZ 2 cÖKvi GKK (Unit) c×wZ e¨envi Kiv nq|

1| lvUg~jK c×wZ (Sexagesimal system) I
2| e„Ëxq c×wZ (circular system)

lvUg~jK c×wZ‡Z †KvY cwigv‡ci GKK n‡”Q ÔwWwMÖÕ| GK wWwMÖ‡K mgvb 60 fv‡M fvM K‡i cÖwZ fvM‡K GK wgwbU
(1= one minute) Ges GK wgwbU‡K mgvb 60 fv‡M fvM K‡i cÖwZ fvM‡K GK †m‡KÛ (1 = one second)

e‡j|

Aciw`‡K e„Ëxq c×wZ‡Z GK ‡iwWqvb (Radian) ‡KvY‡K †KvY cwigv‡ci GKK aiv nq| ‡Kv‡bv e„‡Ëi e¨vmv‡a©i
mgvb Pvc H e„‡Ëi †K‡›`ª †h †KvY Drcbœ K‡i ‡mB †KvY‡K GK †iwWqvb †KvY e‡j|

‡Kv‡bv †Kv‡Yi w·KvYwgwZK gvb †ei Kivi Rb¨ K¨vjKz‡jU‡ii Angle unit, Degree (wWm‡cøi Dci †QvU D
wPý) ‡Z Av‡Q wKbv Zv †Lqvj ivL‡Z n‡e| hw` bv _v‡K Zvn‡j SET UP (qw) e¨envi K‡i cÖ‡qvRb
Abyhvqx cwieZ©b Ki‡Z n‡e| Angle Unit, wWMÖx‡Z _vKvKvjxb †h†Kv†bv †Kv‡Yi w·KvYwgwZK AbycvZ (wWMÖx
GK‡K) Lye mn‡R wb‡Pi w¯Œ‡bi g‡Zv K‡i †ei Kiv hvq-

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