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Grade 12th passAlgebra

m=2-(3)^(1/2)
Find the value of (m^6+m^5+m^4+1)/m^3

Profile image of Aditi
11 Years agoGrade 12th pass
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7 Answers

Profile image of SHAIK AASIF AHAMED
11 Years ago
Hello student,
Please find the answer to your question below
as m=2-\sqrt{3}
m2=7-4\sqrt{3}
m3=26-15\sqrt{3}
1/m3=26+15\sqrt{3}
Given (m6+m5+m4+1)/m3=m+m2+m3+1/m3
=2-\sqrt{3}+7-4\sqrt{3}+26-15\sqrt{3}+26+15\sqrt{3}
=61-5\sqrt{3}

Profile image of Aditi
11 Years ago
Is there any shorter way to solve this?
i got this question in an aptitude test which had 30 questions for 30 minutes.. so i am supposed to solve this in like a minute or so.. 
 
Profile image of Aditi
11 Years ago
is there any shorter way of solving this? 
 
Profile image of Aditi
11 Years ago
is therr any shorter way of answering this?
Profile image of mycroft holmes
11 Years ago
Wish I could post the solution, but this site has a primitive editor 
Profile image of mycroft holmes
11 Years ago
m = 2 – 3^(1/2), and so m + 1/m = 4.
 
We can also write this last equation as m^2 = 4m-1
 
Given expression = (m^3+1/m^3) +m^2+m 
 
Now, using the identity: a+b+c = 0 implies a^3+b^3+c^3 = 3abc, we have
 
m + 1/m – 4 implies m^3 + 1/m^3 – 64 =  3 (m) (1/m) (-4) = -12 
 
so that m^3 + 1/m^3 = 64-12 = 52.
 
Also m^2+m = (4m-1)+m = 5m-1 = 9 – 5(2^1/2)
 
Adding up we get the given expressions equals 61 – 5 (2^1/2)
Profile image of SHAIK AASIF AHAMED
11 Years ago
Hello student,
This may help you
m = 2 – 3^(1/2), and rationalising this we get m + 1/m = 4. som^2 = 4m-1
Given equation is= (m^3+1/m^3) +m^2+m
From the identity if a+b+c = 0 gives a^3+b^3+c^3 = 3abc,
we havem + 1/m – 4=0 gives m^3 + 1/m^3 – 64 = 3 (m) (1/m) (-4) = -12
so m^3 + 1/m^3 = 64-12 = 52.
Also m^2+m = (4m-1)+m = 5m-1 = 9 – 5(3^1/2)
so m+m2+m3+1/m3=61 – 5 (3^1/2)