1if the discriminnt of a quadratic equation is 48 then deter
1.if the discriminnt of a quadratic equation is 48, then determine the number and type of solutions of the equation.
2.use the discriminant to determine the number and type of solutions of the equations: 5-4x+12x^2=0
3.simplify: square root of 5y^11 over square root of 2y
4.simplify: (square root of 80y^6) - square root of 20y^6
5. rationalize the denominator: 1 over (suare root 5) + 3
6. Simplify and write your answer in i notation: square root -44
7. Simplify and write your answer in a+bi notation: (15 + 2i) – (18 – 5i)
8.Simplify and write your answer in a+bi notation: 6i(3 – 8i)
9.Find the distance between the points (-3, 5) and (2, 8).
Solution
1. if the discriminnt of a quadratic equation is >0 , so there would be two real roots.
2. 5 - 4x+12x^2=0
discrimnant : b^2 -4ac = (-4)^2 - 4*5*12
= 16 - 240
= -224
if the discriminnt of a quadratic equation is <0 , so there would be two complex roots.
3. sqrt(5y^11)/sqrt(2y)
= 5^1/2*y^11/2 / 2^1/2*y^1/2
= 5^1/2y/2^1/2*y^1/2
=(5/2)^1/2*y^(11/2 -1/2)
=(5/2)^1/2*y^5
4 sqrt(80y^6) - sqrt(20y^6)
= y^3[ sqrt80 - sqrt20 ]
= y^3[2sqrt20 - sqrt20]
= y^3[sqrt20]
= y^3*2sqrt5
= 2y^3sqrt(5)

