Simultaneous Linear EquationsUnit: 08
Ø Basic Algebraic Formulae:
F
(a + b)2 = a2 + 2ab + b2
F
(a – b)2 = a2 – 2ab + b2
F
a2 – b2 = (a – b) (a + b)
F
(a + b)3 = a3 + 3a2b
+ 3ab2 + b3
F
(a – b)3 = a3 – 3a2b
+ 3ab2 – b3
Ø Linear Equation: A
polynomial of degree one is called linear polynomial. Generally ax + b = 0
where a , b
MCQs
If a – b = 5, a+b=7 the find the value of a2
– b2
a) 74
b) 35
c) 2
d) 12
Solution: a2 – b2 = (a – b) (a + b)
a2 – b2 = 5 × 7 (a – b) = 5, (a + b)= 7
a2 – b2 = 35
If a2
– b2=56, a+b=7, then find the value of a–b
a) 28
b) 4
c) 8
d) 7
If x – 1/x = 5 then find the
value of x4 + 1/x4
a)25
b) 625
c) 727
d) 729
