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Prerequisite for addition formula: https://www.youtube.com/watch?v=iHZmi2MHqWc Proof of formula for sin(A+B): https://www.youtube.com/watch?v=BEETggUVMrY Proof of formula for cos(A+B): https://www.youtube.co...
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Answered by Sam G. Maths tutor
5693 Views

How do I know how many roots a quadratic equation has?

Let ax 2 + bx + c = 0 be the equation in question where a,b,c are real numbers with a not equal to 0 (otherwise we would not have a quadratic). If: b 2 - 4ac > 0 then there are two (real) roots b 2 - 4ac ...
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Answered by Amit G. Maths tutor
10295 Views

How do you differentiate (3x+cos(x))(2+4sin(3x))?

Here we have a product of two things, so we will be using the product rule of differentiation. This is: for y=u(x)v(x), where u(x) and v(x) are funtions of x, dy/dx = u'(x)v(x) + u(x)v'(x). So in this case l...
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Answered by Jaisal P. Maths tutor
6023 Views

Given that 346 × 27 = 9342 , work out 34.6 × 2.7

Lets compare the numbers in the question: 34.6 x 2.7 is the same as 346/10 x 27/10 (decimal to fraction) therefore... 34.6 x 2.7 is the same as ( 346 x 27 ) /100 (multiplying top & bottom) so if 346 × 27...
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Answered by Andrew W. Maths tutor
7748 Views

Factorise x² + 10x + 16

This is a quadratic equation. When we are asked to facorise a quadratic equation, we should label the 3 parts of it a, b and c. x² + 10x + 16 a b c so a = 1 , b = 10 , c = 16 Now, we need to find two numbers...
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Answered by Andrew W. Maths tutor
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