A rose is placed 15.0 cm in front of a convex mirror of focal length 10.0 cm.

I assume f= -10cm bc it's convex correct?
giving me (1/-10)-(1/15)=(1/di)?

Thank you

all correct

Ok thank you :)

Yes, you are correct in assuming that the focal length of a convex mirror is negative, so f = -10.0 cm. You can use the mirror formula, which is given by:

1/f = 1/do + 1/di

Where:
- f is the focal length of the mirror (negative in case of a convex mirror)
- do is the object distance (distance between the object and the mirror)
- di is the image distance (distance between the image and the mirror)

In this case, the object distance (do) is 15.0 cm and the focal length (f) is -10.0 cm. Substituting these values into the formula:

1/(-10) = 1/15 + 1/di

Now, you can solve for the image distance (di). Rearranging the equation, we get:

1/di = 1/(-10) - 1/15

To find the value of di, you can simplify the equation and calculate the reciprocal:

1/di = (-3 + 2)/(-30)
1/di = -1/-30
di = -30 cm

Therefore, the image is formed 30.0 cm behind the mirror. The negative sign indicates that the image is virtual and upright.