engineering mathematics MCQ #802

If y = e^x cos(x), then dy/dx = ?

engineering mathematics MCQ #802

  1. Question 1

    Q1. If y = e^x cos(x), then dy/dx = ?

    • A) e^x cos(x) - e^x sin(x)
    • B) e^x cos(x) + e^x sin(x)
    • C) e^x sin(x) - e^x cos(x)
    • D) -e^x sin(x)

    Answer: e^x cos(x) - e^x sin(x)

    Explanation: Using product rule, dy/dx = d(e^x cos(x))/dx = e^x * d(cos(x))/dx + cos(x) * d(e^x)/dx = e^x * (-sin(x)) + cos(x) * e^x = e^x cos(x) - e^x sin(x).