"enerall#$ an e%&ation is said to be o' "#adratic form i' it has the 'orm ax$n % &xn % c ' ( $ (here n is an integer or a 'ra)tion* s&)h as + 4 , 5+2 6 = 0 and
(a m ) n = a mn
#-3 #-32 6 = 0
( ab) n = a nb n
/&adrati) orm&la:
X
= − b ±
n
a = a n b b n
5.
n
an
=a
n
ab
=
3.
n
4.
m n
a
n
n
a
n
b
=
mn
b a
trinomial) 3. hen b2 – 4ac < 0, the roots are imaginary and unequal complex conjugates
he roots: a
X1
1.
log b MN
2.
logb
= log b M +log bN
M = logbM - logb N N logbMN =NlogbM
Important Properties :
1: a 0 2: 3: 4: 5: 6: 7:
a
-n
provided a ≠ 0
=1 1 =
a
n
m
an
=
n
a
m
=
( a) n
m
or e lnb = b a = a implies that m = n log M N implies that M = bN b log M logbN implies that M = N b log bN : log aN = log b a log b 1 !: provided b > 0, b ≠ 1 b log 1 0 = 10: provided b > 0, b ≠ 1 b a logab m
=
=
− b +
b 2
− 4ac
X2
2a
b =− −
b
2
− 4ac
2a
&m &m o' o' the the root roots$ s$ +1 +2 = - ba
Laws of Logarithms:
3.
− 4ac
2a
1. hen b2 – 4ac > 0, the roots are real and unequal . 2. hen b2 – 4ac = 0, the roots are real and equal or quadratic equation is a perfect an b
=
2
he e+pression b2 – 4ac is is )alled the discriminant
Laws of Radicals:
1. 2.
b
b
n
=
=
=
L,E-T C++! +ULTIPLE .LC+/
he lo(est )ommon m<iple
rod&)t o' the roots$ + 1 +2 = )a T)E *I!+IAL T)ERE+
his arra# o' n&mbers is )alled the as)al@s riangle. ;n# lo(er ro( is 'ormed b# adding an# t(o adCa)ent n&mbers o' the &pper ro( and pla)e 1 at both ends so as to 'orm a triangle. as)al@s riangle is &sed to easil# re)all the n&meri)al )oe''i)ients o' the e+pansion o' the po(ers o' a binomial. 8&t 'or large po(ers o' a binomial$ as)al@s riangle be)omes in)onvenientl# to &se. or s&)h$ &se 8inomial heorem. he rth term o' + # n =
Arithmetic +ean
nn-1n-2Dn-r2 r , 1E
+n-r1#r-1
he arithmeti) mean bet(een t(o n&mbers is the n&mber (hi)h (hen pla)ed bet(een
L,E-T C++! +ULTIPLE .LC+/
he lo(est )ommon m<iple
Arithmetic +ean
he arithmeti) mean bet(een t(o n&mbers is the n&mber (hi)h (hen pla)ed bet(een the t(o n&mbers$ 'orms (ith them an arithmeti) progression.
9n general$ 'or n terms$ arithmeti) mean .A+/ = a1 a2 a3 D a n n 0eometric Progression .02P2/
-
)I0)E-T C++! 1ACTR .)C1/
he highest )ommon 'a)tor 'a)tor G? o' several nat&ral n&mbers n&mbers is the the largest nat&ral n&mber (hi)h is a 'a)tor 'a)tor o' o' all the given n&mbers. 9t ma# be 'o&nd b# taFing the prod&)t o' o' all the di''erent prime 'a)tors )ommon to the given n&mbers$ ea)h taFen the smallest n&mber o' times that it o))&rs in an# o' those n&mbers. 9' the given n&mbers have no prime 'a)tors in )ommon$ the G? is de'ined to be 1$ in this )ase the n&mbers are said to be relativel# prime.
The nth term6 a n
a se%&en)e o' terms in (hi)h ea)h term a'ter the 'irst is 'o&nd b# m<ipl#ing the pre)eding term b# a 'i+ed n&mber )alled )ommon ratio. he se%&en)e a1$ a2$ a3 are in ".. i' and onl# i': a2a1 = a3a2 = r
an = a1r n-1
-#m of the first n terms in 02P2
n = a1 1-r n 1-r (here a1 = 'irst term r = )ommon ratio n = n&mber o' terms
+ample: ind the highest )ommon 'a)tor o' 24$ 30$ 1 and 150. ol&tion: 24 = 2+2+2+3$ 30 = 2+3+5$ 1 = 2+3+3$ 150 = 2+3+5+5 G? = 2+3 = 6
Infinite 0eometric Progression
he s&m o' terms in geometri) progression )an be 'o&nd i' the )ommon ratio J r JK1$ -1 K r K 1
PR0RE--I! Arithmetic Progression .A2 P2/
a se%&en)e o' terms in (hi)h ea)h term a'ter the 'irst is obtained b# adding a 'i+ed n&mber to the pre)eding term. - a se%&en)e o' terms in (hi)h an# t(o )onse)&tive terms has a )ommon di''eren)e. hat is$ the se%&en)e a1$ a2$ a3 are in arithmeti) progression i' and onl# i':
5
-
a$ 3 a4 ' a5 3 a$
hat is$ a1$ a2$ a3Dan are in harmoni) progression 9' 1a1$ 1a2$ 1a3D1an 'orm an arithmeti) progression
=
a1
1
−
r
"eometri) Mean he term in bet(een the 'irst and last terms o' the geometri) se%&en)e.
geometri) progression
e%&en)e o' terms (hose re)ipro)al 'orms an arithmeti) progression
52 7ARIATI! i. Direct Variation also dire)t proportion
hat is$ a1$ a2$ a3Dan are in harmoni) progression 9' 1a1$ 1a2$ 1a3D1an 'orm an arithmeti) progression
52 7ARIATI! i. Direct Variation also dire)t proportion
he ive tatements 8elo( Gave ame Meaning "s x increases y increase proportionately y is proportional to x y is directly proportional to x y #aries as x y #aries directly as x
)armonic +ean
9n s#mbols the above statements mean$
1a$ 1+$ 1b → in ;. .
y $ x
hen$ olving 'or +:
9n mathemati)al terms$ # = F+ (here F is )alled the )onstant o' proportionalit# proportionalit# or also )alled the )onstant variation
2+ = 1a 1b
ii. Inverse Variation also indire)t variation
1+ , 1a = 1b , 1+ → )ommon di''eren)e
o'
he 'ollo(ing tatements 8elo( Gave ame Meaning
2+ = a bab
"s x decreases y increase %and #ice #ersa) y is in#ersely proportional to x y #aries indirectly as x
+ = 2aba b )armonic +ean .)+ =
9n s#mbols the above statements mean$
L n 1a1 1a2 1a 3 D 1a n
RATI6 PRPRTI! A!D 7ARIATI! 42 RATI
he ratio o' a n&mber a to another n&mber b is the 'ra)tion ab &s&all# as a:b read a is to b. here a is )alled antecedent and and b is )alled consequent
y $ &'x
9n mathemati)al terms$ # = F+$ + not e%&al to Qero +amples 1. 8o#le@s
$2 PRPRTI!