easy one

Its a very easy question.
it came in my board xams,so i want to confirm the answer.
please help:)

3 Answers

my working
from the convex lens:
u=--20; f=+15
(1/v)-(1/u)=1/f
v=60 cm

image is formed 25 cm to the right of concave wich behave as object now:
u=+25;f=--25cm
(1/v)-(1/u)=1/f
1/v=0;
so v=âˆž;

seems correct to me :)

seems correct to me :)

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