ONLINE TEST 8TH MATHS NUMNERS EX 1.6

Online Test: Exponents and Powers

(1) (-1)^{even integer} =
1
-1
0

(-1)^even = 1. Example: (-1)² = 1

(2) For a ≠ 0, a⁰ =
1
0
a

Any non-zero number raised to the power 0 is 1.

(3) 4^-3 × 5^-3 =
20^-3
9^-6
-20³

(4^-3 × 5^-3) = (4×5)^-3 = 20^-3

(4) (-2)^-7 =
-1/128
128
-128

(-2)^-7 = 1/(-2)⁷ = -1/128

(5) (-1/3)^-5 =
-243
1/243
3⁵

(-1/3)^-5 = (-3)⁵ = -243

(6) If 8^x = 1/64, then x =
-2
2
3

8 = 2³, 64 = 8² ⇒ 1/64 = 8^-2 ⇒ x = -2

(7) Simplified form of (256)^-1/4 × 4² is:
1/4
4
16

256 = 4⁴, so 256^-1/4 = 4^-1. Then 4^-1 × 4² = 4¹ = 4

(8) (3⁷)^-2 =
3⁵
3^-14
3¹⁴

(3⁷)^-2 = 3^7×(-2) = 3^-14

(9) Standard form of 2 × 10^-4 =
0.0002
0.02
0.00002

2 × 10^-4 = 2 × 0.0001 = 0.0002

(10) Scientific form of 123.456 =
1.23456 × 10²
1.23456 × 10^-2
123.456 × 10⁰

123.456 = 1.23456 × 10²