Easy -1.2 This is a straightforward exponential equation requiring only the recognition that 4 = 2^2, leading to 2^x = 2^(4x+2), then equating exponents to get x = 4x + 2, solving to x = -2/3. It's a routine single-technique question worth 3 marks with no conceptual difficulty, making it easier than average.
\(x = -\frac{2}{3}\) or decimal equiv rounding to 0.667
A1
[3]
OR
Answer
Marks
Guidance
Indicate the logs should be taken of both sides
M1
Use the third log law to remove powers
DM1
\(x = -\frac{2}{3}\) or decimal equiv rounding to 0.667
A1
Answer only 3/3
[3]
Write 4 as a power of 2 | M1 |
Write a linear eqn | M1 |
$x = -\frac{2}{3}$ or decimal equiv rounding to 0.667 | A1 | [3]
OR
Indicate the logs should be taken of both sides | M1 |
Use the third log law to remove powers | DM1 |
$x = -\frac{2}{3}$ or decimal equiv rounding to 0.667 | A1 |
Answer only 3/3 | | [3]