1. Let's understand the problem: You mentioned being incorrect for I1 and I3 but did not provide the exact equations or expressions for I1 and I3. 2. To find your error, please provide the full expressions or steps you took for I1 and I3. 3. Without the specific math, I can guide you generally: check if you made any mistakes in algebraic manipulation, sign errors, or incorrect substitutions. 4. Please share the detailed work for I1 and I3 to identify the mistake clearly.