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Can you help me solve the equation x^2+3x-5

We can see right off the bat that this is a quadratic equation. As always with quadratics, it is easiest to see if it factorises first. To factorise, you need to find two numbers that multiply together to cr...
MS
Answered by Mollie S. • Maths tutor
5250 Views

Solve for the coordinates where lines A and B intersect. A: y=x+4 B: y=0.5x+3.5

The point of intersection is a point where the variables y and x will be the same in both A and B equations. This is because the point of intersection has the same coordinates for both lines. So Y A = Y B an...
HP
Answered by Harvey P. • Maths tutor
5054 Views

Solve the equation: 5^(2x+1) = 7, giving your answer correct to four decimal places.

First, we take logs of both sides: log(5^(2x+1))=log(7) Now, using the 3rd law of logs (index rule; using the power as the coefficient), we get: (2x+1)log(5)=log(7) i.e. 2x+1 = (log(7))/(log(5)) = 1.20906......
MS
Answered by Mohamad S. • Maths tutor
10152 Views

Why is the derivative of inverse tan(x) 1/(1+x^2)?

This can be proven by understanding tan(x) and it's inverse as functions, using implicit differentiation, subsitution and by recognising trigonometric identities (or being able to prove them from first princ...
NG
Answered by Neel G. • Maths tutor
7112 Views

Simplify x^2 - 9x + 20

Firstly write out the equation x 2 - 9x + 20 = 0. The aim is to find two numbers that multiply to make 20 and add up to make -9. Look at the constant without any x's , in this case it is 20. We need to work ...
AM
Answered by Amrit M. • Maths tutor
6925 Views