math
(1) Find the H.C.F. and L.C.M. of
(i) 8x2 + 2x – 21 and 10x2 – 11x – 6 (ii) 8 ( x3 + x2 + x ) and 28 ( x5 – x2 )
Soln. (i)
…
☼L.C.M. : A polynomial p(x) is called the L.C.M. of two or more given polynomials, if it is a polynomial of smallest degree which is divided by each one of the given polynomials….
☼ H.C.F. of Polynomials : A polynomial h(x) is called the H.C.F. or G.C.D. of two or more given polynomials, if h(x) is a polynomial of highest degree dividing each one of the given polynomials.
The coefficient of hi…
(4) If m = – 28, and n = 20, find the value of 9m2 + 24mn + 16n2.
Soln. 9m2 + 24mn + 16n2 = ( 3m + 4n )2 = ( – 84 + 80 )2 = 16.
…
(1) If a + b = 9 and a – b = 5, find a2 + b2 and ab.
Soln. 2( a2+b2 ) = (a + b) 2 + (a – b) 2
= (9) 2 + (5) 2
= 1…
☼ Remainder Theorem : If an expression f(x) is divided by (x – a), then the remainder is f(a).
e.g. Is x + 2 a factor of 5x2 – 3x – 14 ?
☼ Factor Theorem : If f(x) is completely divisible by (x – a), then f(a) = 0.
Thus, (x – a) is a factor of f(x)