If x2 + 1/25×2 = 8 3/5, find x + 1/5x.

If x² + 1/25x² = 8 3/5, find x + 1/5x.

Answer :

We know that

(x + 1/5x)² = x² + 1/25x² + 2x (1/5x)

It can be written as

(x + 1/5x)² = x² + 1/25x² + 2/5

Substituting the values

(x + 1/5x)² = 8 3/5 + 2/5

(x + 1/5x)² = 43/5 + 2/5

So we get

(x + 1/5x)² = 45/5 = 9

Here

x + 1/5x = ± √9 = ± 3

More Solutions:

• If (x + 1/x)2 = 3, find x3 + 1/x3.
• If x = 5 – 2√6, find the value of √x + 1/√x.
• If a + b + c = 12 and ab + bc + ca = 22, find a2 + b2 + c2.
• If a + b + c = 12 and a2 + b2 + c2 = 100, find ab + bc + ca.
• If a2 + b2 + c2 = 125 and ab + bc + ca = 50, find a + b + c.
• If a2 + b2 + c2 = 125 and ab + bc + ca = 50, find a + b + c.
• Find the value of ab – bc – ca.
• If a – b = 7 and a2 + b2 = 85, then find the value of a3 – b3.
• Find the product of x and y.
• Find the sum of their cubes.