Question

if x=√3+1/2 find the value of the 4xcube +2x square -8x-4
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Answer 1

Answer:

x=√3+1/2

x-1/2=√3

squaring on both sides

(x-1/2)²=3

4x²+1-x=3

4x²-x-2=0......................(1)

take the lhs and divide it by 4xcube +2x² -8x+7

hence

4xcube +2x² -8x + 7= (4x²-x-2)(x+3/4)+(-21/4x+17/2)

from eq (1)

=0(x+3/4) + (-21/4x+17/2)

=-21/4(√3+1/2) + 17/2

=47-42√3 / 8 ans.

Step-by-step explanation: