(4) Multiply the given polynomials.
(i) 2x ; x?- 2x - 1 (ii) x-1 ; r3+ 2x2 +2
Answers
Answer:
so, the polynomial factors into, x^2 - 2x - 1 = {x - r+} * {x - r-}. x^2 - 2x - 1 = {x - [1 + sqrt(2)]} * {x - [1 - sqrt(2)]}. Carry out the multiplication and you will find that the two sides of this equation are equal.
2)x
3
−2x
2
+4x+5074=0 (given)
r
1
+r
2
+r
3
=
a
−b
=
1
−(−2)
=2 ---(i)
r
1
r
2
+r
2
r
3
+r
3
r
1
=
a
c
=
1
4
=4 ---(ii)
r
1
r
2
r
3
=
a
−d
=
1
−5074
=−5074 ---(iii)
(r
1
+2)(r
2
+2)(r
3
+2)=(r
1
+2)(r
2
r
3
+2r
2
+2r
3
+4)
=r
1
r
2
r
3
+2r
1
r
2
+2r
3
r
1
+4r
1
+2r
2
r
3
+4r
2
+4r
3
+8
=r
1
r
2
r
3
+2(r
1
r
2
+r
2
r
3
+r
3
r
1
)+4(r
1
+r
2
+r
3
)+8
=−5074+2(4)+4(2)+8 [from (i),(ii) and (iii)]
=−5074+8+8+8
=24−5074
=−505.