He needs 100g of the 21% alloy, and 0g of the 15% alloy to attain the 100g of 21% titanium.
4x + 3 + x - 2 +4x +3 +x - 2
5x + 1 + 4x + 3 + x - 2
5x + 1 + 5x + 1
10x + 2
The inverse function of the logarithm is the exponential function:
In fact, the expression means that if you want to obtain x, you have to give y as exponent to e:
So, we can check both expressions:
, because this expression means "I am giving to e the following exponent: a number that, when given as exponent to e, gives x".
On the other hand, you have
, because this expression means "what exponent do I have to give to e to obtain e^x?". Well, you've basically already written it: if you want to obtain e^x, you have to give the exponent x.
So, we've shown that , which proves that and are one the inverse function of the other.
The answer is B) 1:6. If William has $1, Tim has 3 times as much, which means Tim has $3. Marie has 2 times as much as Tim which means she has $6. The ratio would be 1:6 William Marie.