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Expand and simplify (x+5)(x+7)

Front - Outer -Inner -Last (FOIL)
x X x = x^2x X 7 = 7x 5 X x = 5x5 X 7 = 35
7x + 5x = 12x
x^2 + 12x + 35

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find the derivative of f(x) = x^3 + 2x^2 - 5x - 6. Find all stationary points of the function.

Calculate the derivative using the standard rules, in particular (xⁿ)' = nx^n-1.f(x)' = 3x² + 4x - 5Stationary points are...

Answered by Gustas M. • Maths tutor

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Show how you can rewrite (x+1)(x-2)(x+3) into the form of ax^3 + bx^2 + cx + d

Split the first equation into three parts, i.e. (x+1), (x-2) and (x+3). Multiply the first two parts to get x²- x - 2, then multiply the resul...

Answered by Gustas M. • Maths tutor

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Solve simultaneous equations: 3x + y = 12 and 5x + 5y = 30

Make y the subject of equation 1 by subtracting 3x from both sidesy = 12 - 3x
Substitute 12 - 3x for y in equation 25x + 5(12 - 3x) = 305x + 512 - 53x = 305x + 60 -15x = 3060 - 10x = 30 ...

Answered by Tutor162883 D. • Maths tutor

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Find the solutions of the equation: sin(x - 15degrees) = 0.5 between 0<= x <= 180

Consider a sin graph and all the points on the graph which are equal to 0.5. You'll find that, between one period of a positive sin graph, invsin(0.5) may equal 30 degrees or 150 degrees.
The equati...

Answered by Mahir T. • Maths tutor

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