Question

Write the sum of roots of 2x^2-3x-1=0

Answer 1

✏ Answer

The sum of the roots is given by

-b/a = -(-3)/2

✏ 3/2

Answer 2

Hello !!

Is very simple solve your question. See the resolution below.

The formula.

Sum = [(-b + √D)/2a] + [(-b - √D)/2A]

Find the discriminant.

D = b^2 - 4ac

D = (-3)^2 - 4(2)(-1)

D = 9 + 8

D = 17

Now, you put the information of the statement in the formula and find the sum.

Sum = [(-(-3) + √17)/2(2)] + [(-(-3) - √17)/2(2)]

Sum = [(3 + √17)/4] + [(3 - √17)/4]

Sum = [(4(3 + √17) + 4(3 - √17))/16]

Sum = [(4(3 + √17) + 4(3 - √17))/16]

Sum = 24/16

Sum = 12/8

Sum = 6/4

Sum = 3/2

Final result : the sum is 3/2.

I hope I have collaborated !