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4: Section 2.1 Answers

  • Page ID
    103619
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    1. \(y=2\pm\sqrt{2(x^{3}+x^{2}+x+c)}\)

    2. \(\ln (|\sin y|)=\cos x+c; \quad y \equiv k\pi,\quad k=\text{integer}\)

    3. \(-{1\over 5}e^{-5y}={1\over 2}e^{2x}+c\)

    4. \(y=\frac{c}{x-c}; \quad y≡-1\)

    5. \({y\over y-1}=ce^x; \quad y≡1\)

    6. \(\frac{(\ln y)^{2}}{2}=-\frac{x^{3}}{3}+c\)

    7. \(y^{3}+3\sin y+\ln |y|+\ln (1+x^{2})+\tan ^{-1}x=c;\quad y≡0\)

    8. \((y^2-1)^{-1/2}={1\over x}+c;\quad y≡\pm 1\)

    9. \(y=\tan \left(\frac{x^{3}}{3}+c \right)\)

    10. \(y=\frac{c}{\sqrt{1+x^{2}}}\)

    11. \({y-2\over y-1}=ce^{(x^2-2x)/2};\quad y≡1\)

    12. \(y=1+(3x^{2}+9x+c)^{1/3}\)

    13. \(y=2+\sqrt{\frac{2}{3}x^{3}+3x^{2}+4x-\frac{11}{3}}\)

    14. \(y=\frac{e^{-(x^{2}-4)/2}}{2-e^{-(x^{2}-4)/2}}\)

    15. \(xy=e^{-(1+1/x)}\)

    16. \(y^{3}+2y^{2}+x^{2}+\sin x=3\)

    17. \((y+1)(y-1)^{-3}(y-2)^{2}=-256(x+1)^{-6}\)

    18. \(y=-1+3e^{-x^{2}}\)

    19. \({y^2\over y^2+1}={1\over 2}e^{2x^2}\)

    20. \(y≡-1;\quad (-\infty,\infty)\)

    21. \({y-2\over y-1}={1\over 2}e^{-x^2};\quad (-\infty,\infty)\)

    22. \(y=\frac{-1+\sqrt{4x^{2}-15}}{2};\quad ({\sqrt {15}\over 2},\infty)\)

    23. \(y=\frac{2}{1+e^{-2x}}; \quad (-\infty ,\infty )\)

    24. \(y=-\sqrt{25-x^{2}};\quad (-5,5)\)

    25. \(y≡2;\quad (-\infty ,\infty )\)

    26. \(y=3\left(\frac{x+1}{2x-4} \right)^{1/3};\quad (-\infty ,2)\)

    27. \(y=-\sqrt{25-x^2}; \quad (-5,5)\)

    28. \(y=\frac{x+c}{1-cx}\)

    29. \(y=-x\cos c+\sqrt{1-x^{2}}\sin c;\quad y≡1; \:y≡-1\)

    30. \(y=-x+3\pi /2\)

    31. a. \(y={1\over 1-{1\over 2}e^x}; \quad (-\infty,\ln 2)\)
    b. \(y≡0;\quad (-\infty ,\infty )\)

    32. a. \(y={x\over x+1}; \quad (-1,\infty)\)
    b. \(y≡1;\quad (-\infty ,\infty )\)

    33. \(y=1+(x^2+4)^{3/2}; \quad (-\infty,\infty)\)

    34. \(y=\left\{\begin{array}{cc}{1,}&{0<x\leq \sqrt{5}}\\{1-(x^2-5)^{3/2},}&{\sqrt{5}<x<\infty}\end{array} \right.\)


    This page titled 4: Section 2.1 Answers is shared under a not declared license and was authored, remixed, and/or curated by William F. Trench.

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