Question

if x+1/x =3/2 , then the value of 8x³+1/8x³ wil be​

Answer 1

Answer:

Given: (x)+(1/x)=3/2

(4x^2+1)/2x=3/2

4x^2+1=6x

4x^2-6x+1=0

By formula method

x=(3+root5)/4 and (3-root5)/4

And we know that :root 5=2.23 (approx)

So,

x=1.3 and 0.2

Now,

(x^3)+(1/8x^3)=?

First we put x=1.3 then we get

=2.15

And when we put x=0.2 then we get

=15.6

Answer 2

Answer:

-9

Step-by-step explanation:

Given: x+1/x =3/2 ... (1)

To obtain 8, we first need to multiply 2.

2(x + 1/x) = 3

We can get 8(x³ + 1/x³) after cubing both sides.

8(x³ + 3x + 3/x + 1/x³) = 27

From (1)

8(x³ + 9/2 + 1/x³) = 27

8(x³ + 1/x³) + 36 = 27

∴8(x³ + 1/x³) = -9