Optics – Image formation (lenses)

1. The problem statement, all variables and given/known data

A lense with a focal length of ##-48.0cm## forms an image ##17.0cm## to the right of the lense. Where is the object positioned?

2. Relevant equations

$$\dfrac{1}{d_0}+\dfrac{1}{d_i}=\dfrac{1}{f}$$

3. The attempt at a solution

Well, since the focal length is negative, we know that the lense is divergent (concave). The problem statement says that the image is to the right of the lense, so the ##s_i=17cm (>0)##

We can compute the position of the object by using the formula above:

$$\dfrac{1}{d_0}+\dfrac{1}{17}=- \dfrac{1}{48}$$

And doing the calculations, it comes down to:

$$s_0=-12.55$$

However, the solutions say the solution is ##s_0=26.3##. One can get that if we take ##s_i## to be negative, which is wrong, in my opinion. (?)

So, why am I wrong? Or am I correct?

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