The given expressions written in standard form are;
A) 21 × 10⁷
B) 5 × 10²
This is about expression of given algebra in standard form making use of laws of indices.
A) We are given;
(7 × 10⁵) × (3 × 10²)
Now according to the law of indices, when we want to multiply 2 numbers with same bases and different exponents, we retain the bases and add the exponents.
Also, when we want to multiply 2 numbers with different bases and same exponent, we multiply the bases and retain the exponent.
Applying that to our question gives;
(7 × 3)¹ × (10)⁽⁵ ⁺ ²⁾
⇒ 21 × 10⁷
B) We are given;
(2 × 10⁵)/(4 × 10²)
According to the law of indices, when we want to divide 2 numbers with same bases and different exponents, we retain the bases and subtract the exponents.
Also, when we want to divide 2 numbers with different bases and same exponent, we divide the bases and retain the exponent.
Thus;
(2/4)¹ × (10)⁽⁵ ⁻ ²⁾ = 0.5 × 10³
0.5 can also be expressed as; 5 × 10⁻¹
Thus, 5 × 10⁻¹ × 10³ = 5 × 10²
Read more at; brainly.in/question/18681990
