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Can you suggest any useful resources for listening and/or reading practice?

Obviously past papers are key for practice at GCSE. Even old style practice papers are still useful. However it is not enough to just get answers wrong and move on. It is more useful to look up all the vocab...
EK
Answered by Elizabeth K. • French tutor
3427 Views

Prove that tan^2(x)=1/(cos^2(x))-1

tan^2(x)=1/(cos^2(x))-1 Left hand side of the equation (LHS)=tan^2(x) Use the identity tan(x)=sin(x)/cos(x) and substitute it into the LHS LHS=sin^2(x)/cos^2(x) Use the identity sin^2(x)+cos^2(x)=1 and rearr...
PA
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Explain why the trend in ionisation energy changes between group 5 and 6

Group 5 and 6 have a different electronic structure, with group 6 having one extra electron that group 5. If we look at Hunds rule, which states that electrons must occupy orbitals individually before pairin...
KR
Answered by Kavita R. • Chemistry tutor
21939 Views

f(x) = 4x^2 + 8x - 5 ; complete the square to find the turning point of f(x).

4x^2 + 8x - 5 = 0 4(x^2 + 2x - (5/4)) = 0 4((x + 1)^2 - 1^2 - (5/4)) = 0 4((x + 1)^2 - (9/4)) = 0 4(x + 1)^2 - 9 = 0 4(x + 1)^2 - 9 = 0 Turning point is at (-1, -9)
CK
Answered by Charlotte K. • Maths tutor
10101 Views

Solve the simultaneous equations: y=x^2+4x-2, y=x+2

Equations: 1). y=x^2+4x-2 2.)y=x+2 x+2=x^2+4x-2 First put equation 1 in equation 2 0=x^2+3x-4 Make one side of the equation equal to 0 0=(x+4)(x-1) Factorise the equations Equations 3).x+4=0 4). x-1=0 One or...
PA
Answered by Phoebe A. • Maths tutor
3606 Views