Question

Please answer question 9

Answer 1

this is alternative method
solve
x^2-6x+8=0
(x-4)(x-2)=0
hence roots are 4 and 2
put is the equation of alpha beta
=4/2 +2/4
=2+1/2
=5/2

Answer 2

Let a and be are the zeroes of the quadratic polynomial f(x) = x^2 - 6x + 8.

= > We know that sum of zeroes = -b/a

a + b = -(-6)/1

a + b = 6.


= > We know that product of zeroes = c/a

ab = 8/1

ab = 8.

$= \ \textgreater \ Given: \frac{a}{b} + \frac{b}{a}:$

$= \ \textgreater \ \frac{a^2 + b^2}{ab}$

$= \ \textgreater \ \frac{(a + b)^2 - 2ab}{ab}$

$= \ \textgreater \ \frac{(6)^2 - 2(8)}{(8)}$

$= \ \textgreater \ \frac{36 - 16}{8}$

$= \ \textgreater \ \frac{20}{8}$

$= \ \textgreater \ \frac{5}{2}$



Hope this helps!