191)

If x² + 8y² - 12y - 4xy + 9 = 0, then the value of (7x - 8y) is:

SSC CPO 2020

A)

12

B)

9

C)

21

D)

5

192)

If x² - 5x + 1 = 0, then the value of \(\left(x^4 + \frac 1 {x^2}\right) \)\(\div \left(x^2 + 1\right)\) is:

SSC CPO 2020

A)

25

B)

21

C)

22

D)

24

193)

If x + y + z = 19, xyz = 216 and xy + yz + zx = 114, then the value of x³ + y³ + z³ + xyz is:

SSC CPO 2020

A)

1225

B)

1441

C)

577

D)

361

194)

If x² – 3x + 1 = 0, then the value of \( (x^4 + \frac{1}{x^2}) \div (x^2+1) \) is:

SSC CPO 2020

A)

9

B)

5

C)

6

D)

7

195)

If x + y + z = 17, xyz = 171 and xy + yz + zx = 111, then the value of \(\sqrt[3]{{(x^3+y^3+z^3+xyz)}} \) is:

SSC CPO 2020

A)

0

B)

-4

C)

4

D)

-64

196)

The students of a class donated a sum of Rs. 2,809 to the Fund. Each student donated as many rupees as the number of students in the class. The number of students in the class is:

SSC CPO 2020

A)

51

B)

53

C)

49

D)

47

197)

If x² + 8y² + 12y - 4xy + 9 = 0, then the value of (7x + 8y) is:

SSC CPO 2020

A)

9

B)

-33

C)

-9

D)

33

198)

If a² + b² + c² + 84 = 4(a - 2b + 4c), then \(\sqrt {ab - bc + ca}\) is equal to:

SSC CPO 2020

A)

\(4\sqrt {10}\)

B)

\(5\sqrt {10}\)

C)

\(2\sqrt {10}\)

D)

\(\sqrt {10}\)

199)

If a³ + b³ = 217 and a + b = 7, then the value of ab is:

SSC CPO 2020

A)

-1

B)

6

C)

-6

D)

7

200)

If x + y + z = 13, x² + y² + z² = 133 and x³ + y³ + z³ = 847, then the value of \(\sqrt[3]{{xyz}}\) is:

SSC CPO 2020

A)

-9

B)

-6

C)

7

D)

8