Express $9^{x+1}$ in the form $3^y$, giving $y$ in the form $ax + b$, where $a$ and $b$ are constants. - Edexcel - A-Level Maths Pure - Question 4 - 2016 - Paper 1
Question 4
Express $9^{x+1}$ in the form $3^y$, giving $y$ in the form $ax + b$, where $a$ and $b$ are constants.
Worked Solution & Example Answer:Express $9^{x+1}$ in the form $3^y$, giving $y$ in the form $ax + b$, where $a$ and $b$ are constants. - Edexcel - A-Level Maths Pure - Question 4 - 2016 - Paper 1
Step 1
Express $9^{x+1}$ as $3^y$
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Answer
First, note that 9 can be expressed as a power of 3:
9=32.
Thus, we can rewrite 9x+1 as:
9x+1=(32)x+1=32(x+1)=32x+2.
Step 2
Write in the form $3^y$
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