Original post by ckfeister
c) α = 5, β = -¾
Use the method shown in the above example to write down the equations whose roots are: (α+β and αβ)
I get...
α+β= 5/4
αβ= -15/4
((times by 4 to remove the fractions))
The answer is
4x2 -17x - 15 = 0
What did I do wrong?
Use the method shown in the above example to write down the equations whose roots are: (α+β and αβ)
I get...
α+β= 5/4
αβ= -15/4
((times by 4 to remove the fractions))
The answer is
4x2 -17x - 15 = 0
What did I do wrong?
On the next question,
α = -3, β = -4
I get
α+β= -7
αβ= 12
The answer is
x2 + 7x + 12 = 0
What did I do wrong here?
α = -3, β = -4
I get
α+β= -7
αβ= 12
The answer is
x2 + 7x + 12 = 0
What did I do wrong here?
Original post by Mr M
Nevermind, what about the above?
Original post by ckfeister
How do I do then?
Type in into your calculator?
Original post by Mr M
Type in into your calculator?
I noticed after looking at it, I have dyslexic so I can't find these on own for some reason... also what about the other question? I got -7x not +7x (question is above)
Original post by ckfeister
what about the other question? I got -7x not +7x (question is above)
This is the third time you have had the same problem at this final step on different threads so I don't think you are getting it. You always need to change the sign of the sum.
It's because (note the negative sign).
Original post by Mr M
This is the third time you have had the same problem at this final step on different threads so I don't think you are getting it. You always need to change the sign of the sum.
It's because (note the negative sign).
It's because (note the negative sign).
So even when shown on I still use negative sign? I know
Original post by ckfeister
So even when shown on I still use negative sign? I know
To form the quadratic equation do this:
(sum of roots) (product of roots)
This will always give you the right answer.
Original post by Mr M
To form the quadratic equation do this:
(sum of roots) (product of roots)
This will always give you the right answer.
(sum of roots) (product of roots)
This will always give you the right answer.
thx
Original post by ckfeister
P = FV
Answer is ( 31 )
( -93 1/2 )
How comes I got -42 1/2 on bottom?
(27*-2) + (5*17) = 31
(0*-2) + (-5 1/2*17) = -42.5
??
Answer is ( 31 )
( -93 1/2 )
How comes I got -42 1/2 on bottom?
(27*-2) + (5*17) = 31
(0*-2) + (-5 1/2*17) = -42.5
??
It's your dyslexia again. You have read a five as a two.
Original post by Mr M
It's your dyslexia again. You have read a five as a two.
Nevermind found it, thx again...
(edited 7 years ago)
Original post by ckfeister
Where?
Negative five point five times seventeen.
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