+0  
 
-1
76
3
avatar

Let a and b be the solutions to 5x^2 - 11x + 4 = 0. Find 1/(a + 1) + 1/(b + 1).

 Jan 21, 2022
 #1
avatar+13561 
+1

 Find 1/(a + 1) + 1/(b + 1).

 

Hello Guest!

 

\(5x^2 - 11x + 4 = 0\\ x^2-2.2x+0.8=0\\ x=1.1\pm \sqrt{1.21-0.8}\\ x=1.1\pm \sqrt{0.41}\\ a=1.1+ \sqrt{0.41}\\ b=1.1- \sqrt{0.41}\\\)

\(\frac{1}{a+1}+\frac{1}{b+1}=0.364921+0.685078=1.05\)

laugh  !

 Jan 22, 2022
 #2
avatar+360 
+1

\(5x^2-11x+4=0\)

\(x_{1,\:2}=\frac{-\left(-11\right)\pm \sqrt{\left(-11\right)^2-4\cdot \:5\cdot \:4}}{2\cdot \:5}\)

\(x_{1,\:2}=\frac{-\left(-11\right)\pm \sqrt{41}}{2\cdot \:5}\)

\(x_1=\frac{-\left(-11\right)+\sqrt{41}}{2\cdot \:5},\:x_2=\frac{-\left(-11\right)-\sqrt{41}}{2\cdot \:5}\)

\(x=\frac{11+\sqrt{41}}{10},\:x=\frac{11-\sqrt{41}}{10}\)

1/(a+1)=\(\frac{21-\sqrt{41}}{40}\)

1/(b+1)=\(\frac{21+\sqrt41}{40}\)

total=\(\frac{21}{20}\)

 Jan 22, 2022
edited by XxmathguyxX  Jan 22, 2022
 #3
avatar+360 
0

wow.. a much easier way!

 Jan 22, 2022

29 Online Users

avatar