kk so i found out the steps involved deriving the thin lens equation, but what i dont get is when you have 2 similar triangles say triangle abd,edf are congruent how does the 2 triangles make it so its di/f-1. so what im basically asking is can someone thourougly explain to me whats going on in the steps to deriving the thin lens equation thnx.(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Optics Thin Lens Equation

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