How do you simplify \[4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}}\] and write it using only positive exponents?
Answer
612.9k+ views
Hint: We use the property of exponents that states that we can add the powers present on the numbers having the same bases. Here we have the same base ‘a’ and ‘b’, so we add the powers and calculate the value in power. Separate the constant values, values with base ‘a’ and with base ‘b’ and then solve.
* If a, m and n are any integer values then \[{a^m} \times {a^n} = {a^{m + n}}\]
* Any number having power 0 can be written as equal to 1 i.e. \[{a^0} = 1\]
Complete step by step solution:
We have to write the value of \[4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}}\]using a positive exponent
We know that when the bases are the same we can add the powers present in the numbers.
Collect the values with same variables
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (4 \times 3)({a^3} \times {a^{ - 4}})({b^2} \times {b^{ - 3}})\]
Here we can write the value of the product by adding the powers .
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12)({a^{3 - 4}})({b^{2 - 3}})\]
Add the values in power
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12)({a^{ - 1}})({b^{ - 1}})\]
We know we can write \[{x^{ - 1}} = \dfrac{1}{x}\]
Then we can write right hand side of the equation using inverse
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12) \times \dfrac{1}{a} \times \dfrac{1}{b}\]
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = \dfrac{{12}}{{ab}}\]
\[\therefore \]The value of \[4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}}\]using a positive exponent is \[\dfrac{{12}}{{ab}}\].
Note: Many students make mistake of writing the final answer as \[12{a^{ - 1}}{b^{ - 1}}\], we know any value having negative power in the exponent can be written as value with same power but in the denominator. Keep in mind we are asked in the question to write the value using positive number in the exponent which means we have to write the value in exponent form, so we write the value \[{a^{ - 1}}\] and \[{b^{ - 1}}\] in form of fraction where we write ‘a’ and ‘b’ in the denominator.
* If a, m and n are any integer values then \[{a^m} \times {a^n} = {a^{m + n}}\]
* Any number having power 0 can be written as equal to 1 i.e. \[{a^0} = 1\]
Complete step by step solution:
We have to write the value of \[4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}}\]using a positive exponent
We know that when the bases are the same we can add the powers present in the numbers.
Collect the values with same variables
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (4 \times 3)({a^3} \times {a^{ - 4}})({b^2} \times {b^{ - 3}})\]
Here we can write the value of the product by adding the powers .
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12)({a^{3 - 4}})({b^{2 - 3}})\]
Add the values in power
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12)({a^{ - 1}})({b^{ - 1}})\]
We know we can write \[{x^{ - 1}} = \dfrac{1}{x}\]
Then we can write right hand side of the equation using inverse
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = (12) \times \dfrac{1}{a} \times \dfrac{1}{b}\]
\[ \Rightarrow 4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}} = \dfrac{{12}}{{ab}}\]
\[\therefore \]The value of \[4{a^3}{b^2}.3{a^{ - 4}}{b^{ - 3}}\]using a positive exponent is \[\dfrac{{12}}{{ab}}\].
Note: Many students make mistake of writing the final answer as \[12{a^{ - 1}}{b^{ - 1}}\], we know any value having negative power in the exponent can be written as value with same power but in the denominator. Keep in mind we are asked in the question to write the value using positive number in the exponent which means we have to write the value in exponent form, so we write the value \[{a^{ - 1}}\] and \[{b^{ - 1}}\] in form of fraction where we write ‘a’ and ‘b’ in the denominator.
Recently Updated Pages
What are the two major island groups in India class 9 social science CBSE

What is Jhum cultivation class 9 biology CBSE

Write an Article on Save Earth Save Life

Silk is obtained from of the silk moth APupa BLarva class 9 chemistry CBSE

Write chemical formulas of the following compounds class 9 chemistry CBSE

The Indo Gangetic Plains of India are fertile due to class 9 social science CBSE

Trending doubts
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Who was referred to as Amitraghata by the Greeks AChandragupta class 9 social science CBSE

Difference Between Plant Cell and Animal Cell

What is the full form of pH?

On an outline map of India show its neighbouring c class 9 social science CBSE

What is pollution? How many types of pollution? Define it

