Answer :
The product of (2j + 7)(2j - 7) is [tex]\rm 4j^2-49[/tex].
Given
The product mentally;
What is multiplication?
Multiplication is the process of calculating the product of two or more numbers.
The multiplication of numbers say, ‘a’ and ‘b’, is stated as ‘a’ multiplied by ‘b’.
The product of (2j + 7)(2j - 7) is given by
[tex]\rm =(2j + 7)\times (2j - 7)\\\\= 2j(2j-7)-7(2i-7)\\\\= 4j^2+14j-14j+49\\\\=4j^2-49[/tex]
Hence, the product of (2j + 7)(2j - 7) is [tex]\rm 4j^2-49[/tex].
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