Basicly, ive got the following: 8^2.5 times 2^-0.5 On the mark scheme, it changes the 8^2.5 to 2^7.5 I don't understand how it does this step. Can anyone explain?
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Hello, Originally Posted by nugiboy Basicly, ive got the following: $\displaystyle 8^[2.5] * 2^[-0.5]$ On the mark scheme, it changes the $\displaystyle 8^[2.5]$ to $\displaystyle 2^[7.5]$ I don't understand how it does this step. Can anyone explain? $\displaystyle 8=2^3$ And you know that $\displaystyle (a^b)^c=a^{bc}$ Plus, $\displaystyle a^b a^c=a^{b+c}$ This is all you need for getting from one formula to another.
Originally Posted by nugiboy Basicly, ive got the following: $\displaystyle 8^[2.5] * 2^[-0.5]$ On the mark scheme, it changes the $\displaystyle 8^[2.5]$ to $\displaystyle 2^[7.5]$ I don't understand how it does this step. Can anyone explain? $\displaystyle 8^{2.5} = (2^3)^{2.5} = 2^{3\cdot{2.5}} = 2^{7.5}$ It's just rules of exponents.
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