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Find the values of k for which the equation (2k-3)x^2-kx+(k-1) has equal roots

We know that an equation has equal roots if the sqrt(b^2-4ac) term in the quadratic equation is equal to zero. Therefore using this information we can form an expression for k to be (-k)^2-4(2k-3)(k-1)=0. Fr...
EH
Answered by Eliott H. • Maths tutor
13949 Views

P(A)=0.2, P(A|B) = 0.3 and P(AuB)=0.6. Find i P(B) ii P(B'|A')

i. P(AuB) = P(A) + P(B) - P(AnB) P(AnB) = P(A|B)P(B) = 0.3P(B) P(AuB) = P(A) + 0.7 P(B) --> 0.6 = 0.2 + 0.7 P(B) --> P(B) = 4/7 ii. P(B'|A') = P(A'nB')/P(A') P(A'nB') = 1 - P(AuB) P(B'|A') = 0.4/0.8 = 1/2
WS
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Briefly describe the concept of electronegativity and explain why CCl4 is a non-polar molecule

Electronegativity is the tendency of an atom to attract a pair of electrons in a covalent bond. The Pauling scale assigns values to this tendency for each element in the periodic table ranging from the lowes...
SS
Answered by Samora S. • Chemistry tutor
26621 Views

Earth is being added to a pile so that, when the height of the pile is h metres, its volume is V cubic metres, where V = (h6 + 16) 1 2 − 4.Find the value of dV/dh when h = 2.

As V=(h 6 +16) 1/2 -4 , the chain rule can be used to calculate dV/dh. dV/dh=3h 5 (h 6 +16) -1/2 h=2 can be substituted in to find the solution. 3 2 5 (2 6 +16) -1/2 =10.73
LK
Answered by Lewis K. • Maths tutor
6804 Views

Explain a few problems the UK economy has endured or is expected to endure as a result of the Brexit Referendum.

Students would be expected to focus on the exchange rate effect - this is quite a useful effect since it allows students to explore the conflicting effects on exporters and importers. It is a nice way to bri...
MP
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