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Solve the simultaneous equations x + y = 3 and x^2 + y^2 = 5

Find an expression for y y = 3 - x sub this into the second equation x^2 + (3 - x)^2 = 5 then expand the brackets x^2 + x^2 - 6x + 9 = 5 simplify 2(x^2 - 3x + 2) = 0 factorise 2(x - 2)(x - 1) = 0 so x = 2, 1...
KW
Answered by Kate W. • Maths tutor
16782 Views

y = 2x^3 + 15x^2 + 24x + 10 Find the stationary points on this curve and determine their nature

First differentiate the function to obtain dy/dx = 6x^2 + 30x + 24 Then set this equal to 0 and solve to find the x values of the stationary points 6x^2 + 30x + 24 = 0 6(x^2 + 5x + 4) = 0 6(x +1)(x+4) = 0 th...
KW
Answered by Kate W. • Maths tutor
10696 Views

In a sale, the original price of a bag was reduced by 1/5. The sale price of the bag is £29.40. Work out the original price.

£29.40 represents 4/5 of xThus to find x, we must multiply 29.40 by 5/4: 29.40/4 = 7.35 (this is 1/5) 7.35 x 5 = 36.75 (this is 5/5, the original price) Original price = £36.75
RW
Answered by Robert W. • Maths tutor
4728 Views

Show that (1 - cos(2x)) / (1 + cos(2x)) = sec^2(x) - 1

First, take the side of the equation that looks most complicated because it often needs simplifying. This is the LHS in this case. The LHS has cos(2x) twice - therefore the double angle formula probably appl...
LG
Answered by Louis G. • Maths tutor
7434 Views

Integrate 5(x + 2)/(x + 1)(x + 6) with respect to x

This term cannot be integrated in the form that it is in. We will have to do some algebraic manipulation to rewrite it. The term can be split into partial fractions because the denominator of the term has be...
LP
Answered by Lata P. • Maths tutor
3695 Views