General math formula.General math formula
a✓+2ab+b✓=(a+b)✓-4ab
a✓-2ab+b✓=(a-b)✓+4ab
a✓-b✓=(a+b)(a-b)
a✓+b✓=(a+b)✓-2ab
=(a-b)✓+2ab
=1/2{(a+b)✓+(a-b)✓}
=1/4{(a+b)✓-(a-b)✓}
4ab= (a+b)✓-(a-b)✓
a-b=(a+b/2)-(a-b/2)
(a+b+c)=a✓+b✓+c✓+2ab+2bc+2ca
(a✓+b✓+c✓)=(a+b+c)✓-2(ab+bc+ca)
2(ab+bc+ca)=(a+b+c)✓-(a✓+b✓+c✓)
(a+b)3 = a3+ 3a✓b+3ab✓+b3
(a-b)3=a3-3a✓b+3ab✓-b3
a3+b3=(a+b)3-3ab(a+b)=(a+b)(a✓-ab+b✓)
a3-b3=(a-b)3+3ab(a-b)=(a-b)(a✓+ab+b✓)
1+2+3. n(n+1)/2 1✓+2✓+3✓ 1/6n(n+1)(2n+1)
13+23+33 .{ n(n+1)/2}✓
loga 1= o
loga a= 1
logam/n = loga+mlogan
loga(mn)=loga-mlogn
Busy : a:b =c:d then a/b =c/d now b/a= d/c
Same multiple: a/b = c/d then a/c= b/d
Plus or adding: a/b c/d then a+b/b c+d/d
Minus : a/b c/d then a-b/b c-d/d
Minus and plus: a/b b/c then a+b/a-b c+d/c-d
a/b c/d e/f g/h হলে a+c+e+g/b+d+f+h
a,b,c equal to a/b b/c then b✓=ac that means a:b = b: c
P = p ×r×time/100
P= 100×r/time×r
Pi= 100×i/(time×r)+100
R = 100×i/p×time
Time =100×i/p×rate
Circle =p(1+r/100) year
Favourable of boat = speed of bot + efflux of speed.
Unfavourable of boat =speed of boat - efflux of speed
Length of Train+ length of platform
If two train speed same side running then it said relative speed.
Two train running same side it will be minus between train speed .
Two train running speed opposition side so two train speed will be plus in.
