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Show that 2tan(th) / (1+tan^2(th)) = sin(2th), where th = theta

We have 2tan(th) / (1 + tan^2(th)) = sin(2th) We know that tan(A) = sin(A) / cos(A), and 1 + tan^2(A) = sec^2(A) Therefore => (2sin(th) / cos(th)) / sec^2(th) => 2sin(th)*cos^2(th) / cos(th) => 2sin...
IC
Answered by Ian C. • Maths tutor
4334 Views

Use logarithms to solve the equation 3^(2x+1) = 4^100

We have 3^(2x+1) = 4^100 => log(3^(2x+1)) = log(4^100) => (2x+1)log(3) = 100log(4)
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Answered by Ian C. • Maths tutor
7351 Views

Discuss the advantages and disadvantages of soft and hard engineering as a river flood management strategy

Outline some of examples of soft and hard engineering techniques as well as their definition. Soft engineering advantages include: Relatively cheap, low maintenance, environmentally friendly and 'green', wor...
DM
Answered by Daniel M. • Geography tutor
17589 Views

2.11g of MgCl2 is added to 30cm3 of water. Find the concentration of chloride ions in the solution.

M r of MgCl 2 = 24.3 + 2(35.5) = 95.3 Moles added = 2.11/95.3 = 0.02214 Mol of cl - added = 2 0.02214 = 0.04428 Conc = 0.04428/(30 10 -3 ) = 1.48 moldm -3
JS
Answered by James S. • Chemistry tutor
3338 Views

Give one advantage and one disadvantage of laboratory experiments.

A question like this is likely to be worth 2-4 marks. In order to answer the question fully, you will need to state the advantage or disadvantage and then explain your reasoning. An advantage of laboratory e...
RD
24338 Views