3²×5, 2⁴×5, 2²×3×5×7, 5⁴ and 3⁴ are the index notations of the numbers 45, 80, 420, 625 and 81 respectively. This can be obtained by taking the factors of these numbers and wring as the powers as shown below.
It is a method of representing numbers and variables that are multiplied by themselves a number of times.
For example, 7³, a²
The given numbers can be represented as the following:
(1) 45 =3×3×5 = 3²×5
(2) 80 =2×2×2×2×5 = 2⁴×5
(3) 420 =2×2×3×5×7 = 2²×3×5×7
(4) 625 =5×5×5×5 = 5⁴
(5) 81 =3×3×3×3 = 3⁴
Hence 3²×5, 2⁴×5, 2²×3×5×7, 5⁴ and 3⁴ are the index notations of the numbers 45, 80, 420, 625 and 81 respectively.
Learn more about index notation here:
brainly.com/question/13157393
#SPJ4
