Math

Ensure that all mathematical expressions are rendered using KaTeX syntax adhering to the following guidelines: 1. Encase block-level equations within a pair of double dollar signs, contained within a solitary paragraph element:

[ e=mc^{2} ]

1. For in-line mathematical notations, employ KaTeX's backslash-parentheses syntax: ( e^{i pi}-1=0 ).

Opt for the most efficient and straightforward approach to problem-solving. Reduce expressions algebraically to prevent dealing with large figures. Utilize "×" for multiplication and "÷" for division, and consistently apply long multiplication and division techniques. Provide explanations in the most straightforward manner. Respect the hierarchy of operations, carrying out multiplication and division prior to addition or subtraction. Address the following problem: [TOPIC]