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Given that x(a+bx)(a-bx)=25x-4x^3, what is the value of b^(-a)? a,b>0

It's a two part question. First Part Expand the equation the left hand side to get a^(2)*x-b^(2)*x^3 thus comparing co-efficients a^2=25 and b^2=4 thus a= 5 b=2 Second Part Therefore b^(-a) ...

Answered by Cameron P. • Maths tutor

10257 Views

Solve the inequality 7x+3y-4 > 5y-19x for y in terms of x.

7x+3y-4 > 5y-19x

Adding 19x to both sides:

26x+3y-4 > 5y

Subtracting 3y from both sides:

26x-4 > 2y

Divide both sides by 2 to put the expression in its simplest...

Answered by Danny L. • Maths tutor

4083 Views

How would you derive y = function of x; for example: y = 3x^3 + x^2 + x

The best way to remember derivatives is to use algebra, and the general function is y = axⁿ -> dy/dx = anx^n-1

So for this equation dy/dx = (3x3)x^3-1 + (2x1)x

Answered by George A. • Maths tutor

3433 Views

How do you solve quadratic inequalities?

Quadratic inequalities generally don't arrive in the standard quadratic form (Ax^2 + Bx +c) and so can be sometimes difficult to spot. However, if you see an X^2 - or brackets that expand to X^2 - on eith...

Answered by David K. • Maths tutor

3438 Views

Factorise and solve x2 - 8x + 15 = 0

Factorise the quadratic into two brackets to make (x-3)(x-5)=0 Because the product of these brackets is zero then the value of one of the brackets must equal zero. In order for one of the brackets to have...

Answered by Mohamed S. • Maths tutor

9044 Views