simplification Model Questions & Answers, Practice Test for ibps rrb po officer scale 1 prelims 2024

Answer: (b)

$x^8 + 1/{x^8}$ = 47

$(x^4 + 1/{x^4})^2 = x^8 + 1/{x^8} + 2$

⇒$x^4 + 1/{x^4} = √{47 + 2} = 7$

$(x^2 + 1/{x^2})^2 = x^4 + 1/{x^4} + 2$

⇒$x^2 + 1/{x^2} = √{7 + 2}$ = 3

⇒$(x^2 + 1/{x^2})^3 = x^6 = 1/{x^6} + 3 (x^2 + 1/{x^2})$

⇒$x^6 + 1/{x^6} = (3)^3$ - 3 (3) = 18

Answer: (b)

? = 1896 ÷ 29 + 445

= $1896/29$ + 445

= 65.4 + 445 = 510.4

≈ 510

Answer: (a)

${(x^2 + y^2)(x - y) - (x - y)^3}/{x^2y - xy^2}$

= ${x^3 + xy^2 - x^2y - y^3 - (x^3 - y^3 - 3x^2y + 3xy^2)}/{x^2y - xy^2}$

= ${x^3 + xy^2 - x^2y - y^3 - x^3 + y^3 + 3x^2y - 3xy^2}/{x^2y - xy^2}$

= ${2x^2y - 2xy^2}/{x^2y - xy^2} = {2(x^2y - xy^2)}/{x^2y - xy^2}$ = 2

Answer: (a)

Let S = {... – 6, – 4, – 2, 0, 2, 4, 6, ...}

I. Now, 2 + (–2) = 0 ∈ S, it is applied.

II. Now, – 2 –2 = –4 ∈ S, it is applied.

III. Now, – 4 × (4) = –16 ∈ S, it is applied.

IV. Now, –4 ÷ 4 = –1 ∉ S, it is not applied.

Answer: (d)

$(84)^2/√{?}$ =168

$√{?}$ = ${84 × 84}/168 $ =42

⇒ ? = $(42)^2$ = 1764