3. By what number should [tex]\left(\frac{1}{2}\right)^{-1}[/tex] be multiplied so that the product is [tex]\left(\frac{-5}{4}\right)^{-1}[/tex]?



Answer :

Sure, let's break this down step-by-step to find the number by which we should multiply [tex]\(\left(\frac{1}{2}\right)^{-1}\)[/tex] to get [tex]\(\left(\frac{-5}{4}\right)^{-1}\)[/tex].

1. Calculate [tex]\(\left(\frac{1}{2}\right)^{-1}\)[/tex]

Raising a fraction to the power of [tex]\(-1\)[/tex] is equivalent to taking its reciprocal.

[tex]\[ \left(\frac{1}{2}\right)^{-1} = \frac{1}{\frac{1}{2}} = 2 \][/tex]

2. Calculate [tex]\(\left(\frac{-5}{4}\right)^{-1}\)[/tex]

Again, raising a fraction to the power of [tex]\(-1\)[/tex] is equivalent to taking its reciprocal.

[tex]\[ \left(\frac{-5}{4}\right)^{-1} = \frac{1}{\frac{-5}{4}} = \frac{4}{-5} = -0.8 \][/tex]

3. Find the number that when multiplied by [tex]\(2\)[/tex] gives [tex]\(-0.8\)[/tex]

Let [tex]\(x\)[/tex] be the number we are looking for. We need to solve for [tex]\(x\)[/tex] in the equation:

[tex]\[ 2 \cdot x = -0.8 \][/tex]

Solving for [tex]\(x\)[/tex],

[tex]\[ x = \frac{-0.8}{2} = -0.4 \][/tex]

So, the number by which [tex]\(\left(\frac{1}{2}\right)^{-1}\)[/tex] should be multiplied so that the product is [tex]\(\left(\frac{-5}{4}\right)^{-1}\)[/tex] is [tex]\(-0.4\)[/tex].