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Solve 7x - 14 = 4x + 7

Like all equations, you're going to start off by getting all the x's on the same side of the = side and all the rest on the other side. So we start off with 7x-14=4x+7. Moving the x's to one side means that ...
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Answered by Daan F. • Maths tutor
9423 Views

Find the value of 4a + 3b when a=2 and b=5

This question is asking us to place a number in the place of their corresponding letter, so as the letter a is attached to the number two, whenever we see the letter a in the equation we would replace it wit...
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Answered by Roisin M. • Maths tutor
15793 Views

Express 5cosx - 3sinx in the form Rcos(x+a).

cos(x+a)=cosxcosa-sinxsina so cosa=5 sina=3 which means tana=3/5 a=0.54 RADIANS R=sqrt(5 2 +3 2 ). =sqrt(34) so sqrt(34)cos(x+0.54)
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Answered by Elizabeth H. • Maths tutor
16632 Views

Simultaneously solve the equations 3x+2y=36 and 5x+4y=64

The easiest way to solve a simultaneous equation is by the method of substitution. First of all, we take the first equation, and rearrange it so that it is in terms of y. Or, in other words, rearrange it so ...
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Answered by Finlay S. • Maths tutor
12606 Views

Differentiate sin(5x) and 3cos(x) and 3tan(5x)

sin cos -sin -cos (down is differentiate and up is integrate) so, y = sin5x dy/dx = 5cos5x y=3cox dy/dx = -3sinx y=3tan5x dy/dx = 15sec 2 (5x) (remember sec(x) is the reciprocal of cos(x))
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Answered by Abi C. • Maths tutor
5304 Views