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If the slope of a line that passes throu...

If the slope of a line that passes through the origin which is tangent to `y= x^(3) + x + 54` is m, then m is equal to

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To find the slope \( m \) of the line that passes through the origin and is tangent to the curve \( y = x^3 + x + 54 \), we can follow these steps: ### Step 1: Find the derivative of the function The slope of the tangent line to the curve at any point is given by the derivative of the function. \[ y = x^3 + x + 54 \] Taking the derivative with respect to \( x \): \[ \frac{dy}{dx} = 3x^2 + 1 \] ### Step 2: Set up the point of tangency Let the point of tangency on the curve be \( (x_1, y_1) \). The coordinates of this point can be expressed as: \[ y_1 = x_1^3 + x_1 + 54 \] ### Step 3: Write the equation of the tangent line The slope of the tangent line at the point \( (x_1, y_1) \) is given by \( \frac{dy}{dx} \) at \( x_1 \): \[ m = 3x_1^2 + 1 \] ### Step 4: Use the point-slope form of the line The equation of the tangent line passing through the origin (0,0) can be written as: \[ y = mx \] At the point of tangency, the coordinates must satisfy both the curve and the line: \[ y_1 = mx_1 \] Substituting \( y_1 \): \[ x_1^3 + x_1 + 54 = (3x_1^2 + 1)x_1 \] ### Step 5: Simplify the equation Expanding the right-hand side: \[ x_1^3 + x_1 + 54 = 3x_1^3 + x_1 \] Now, simplify the equation: \[ x_1^3 + x_1 + 54 - 3x_1^3 - x_1 = 0 \] This simplifies to: \[ -2x_1^3 + 54 = 0 \] ### Step 6: Solve for \( x_1 \) Rearranging gives: \[ 2x_1^3 = 54 \] Dividing both sides by 2: \[ x_1^3 = 27 \] Taking the cube root: \[ x_1 = 3 \] ### Step 7: Find the corresponding \( y_1 \) Now, substitute \( x_1 \) back into the equation for \( y_1 \): \[ y_1 = 3^3 + 3 + 54 = 27 + 3 + 54 = 84 \] ### Step 8: Calculate the slope \( m \) Now, substitute \( x_1 = 3 \) into the slope equation: \[ m = 3(3^2) + 1 = 3(9) + 1 = 27 + 1 = 28 \] Thus, the slope \( m \) is: \[ \boxed{28} \]
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  • The combine equation of the lines passing through the origin and having slopes 3 and 2 is

    A
    `6x^(2)+5xy+y^(2)=0`
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