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let a and b be the solutions to 5x^2-11x+4=x^2-7x + 3

 

Find 1/a + 1/b

 May 1, 2022

Best Answer 

 #1
avatar+309 
+2

Pull over terms to the left side:

4x²-4x+1=0

Factor:

(2x-1)²=0

a would be 1/2. b would also be 1/2.

1/a + 1/b would be 4.

 May 1, 2022
 #1
avatar+309 
+2
Best Answer

Pull over terms to the left side:

4x²-4x+1=0

Factor:

(2x-1)²=0

a would be 1/2. b would also be 1/2.

1/a + 1/b would be 4.

WhyamIdoingthis May 1, 2022
 #2
avatar+2668 
0

Simplify the equation to: 4x24x+1=0

 

We can rewrite 1a+1b as b+aab

 

Using Vieta's, the sum of the roots (a+b) is ba and the product (ab) is ca

 

This means that the sum of the roots is 44=1, and that the product of the roots is 14

 

Substituting this in, we find that 1a+1b=114=4

 May 1, 2022

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