Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

If $(p^2 +\frac{1}{p^2}=14)$, then find the value of $(p^3 +\frac{1}{p^3})$.

Options:

56

60

48

52

Correct Answer:

52

Explanation:

If, x2 + \(\frac{1}{x^2}\) = b

then x + \(\frac{1}{x}\) = \(\sqrt {b + 2}\)

If x + \(\frac{1}{x}\)  = n

then, $x^3 +\frac{1}{x^3}$ = n3 - 3 × n

If $(p^2 +\frac{1}{p^2}=14)$

Then find the value of $(p^3 +\frac{1}{p^3})$

$(p +\frac{1}{p})$ = \(\sqrt {14 + 2}\) = 4

$(p^3 +\frac{1}{p^3})$ = 43 - 3 × 4 = 52