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Find the value of: d/dx(x^2*sin(x))

Use the product rule: d/dx(fg) = f' g + f g' f = x 2 f' = 2x g = sin(x) g' = cos(x) answer = 2xsin(x) + x 2 cos(x)
WR
Answered by Will R. • Maths tutor
10634 Views

Solve x^2+8x-5 = 0 by completing the square.

x 2 + 8x = (x + 4) 2 - 16, so x 2 + 8x - 5 = (x + 4) 2 - 16 - 5 = (x + 4) 2 - 21, so then (x + 4) 2 - 21 = 0 (x + 4) 2 = 21 -----> x + 4 = √21 -------> x = -4 + √21 x = -4 - √21
SJ
Answered by Shadab J. • Maths tutor
13057 Views

Find the equation for the tangent to the curve y^3 + x^3 + 3x^2 + 2y + 8 = 0 at the point (2,1)

As the tangent has the same gradient as the curve at the particular point, we need to find the gradient of the curve. To find the gradient we need to differentiate. Due to there being two variables in this e...
AE
Answered by Aphishek E. • Maths tutor
4867 Views

Find an equation of the straight line that is perpendicular to the straight line x + 3y = 7 and that passes through the point (4,9).

y = 3x - 3
VP
Answered by Vikesh P. • Maths tutor
3905 Views

solve: x^2= 4(x-3)^2

x^2= 4(x^2 - 6x + 9) x^2= 4x^2- 24x + 36 3x^2 - 24x + 36= 0 (x-2)(x-6)=0 x= 2 or x=6
GK
Answered by Ghazn K. • Maths tutor
3835 Views