Let 2x^2+3x+xy=4, and y(4)=10. Find y'(4) using implicit differentiation I got the derivative, y'=-(4x+y+3)/x, but when I solve for y'(4), I'm left with a "y" in the answer, and I guess that's not correct.
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Originally Posted by JamieG Let 2x^2+3x+xy=4, and y(4)=10. Find y'(4) using implicit differentiation I got the derivative, y'=-(4x+y+3)/x, but when I solve for y'(4), I'm left with a "y" in the answer, and I guess that's not correct. We are told that $y(4)=10$ so does $y'(4)=\dfrac{4\cdot4+y(4)+3}{4}~?$
That makes sense! I figured it would be something simple that I was missing.