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Why do the atomic radii of the elements decrease across a period on the periodic table.

It may seem counterintuative that as the elemets' atomic numbers increase their atomic radii decrease. This is due to the increased electrostatic attraction (coulombic interaction) between nucleus and valenc...
DH
Answered by Daniel H. • Chemistry tutor
4189 Views

Find the value of the discriminant of x2 + 6x + 11

For a quadratic equation in the form ax^2+bx+c=0 the determinant is given by b^2-4ac and is used to help identify the types of roots of the equation. In this case, the determinant is (6)^2-4(1)(11) which is ...
EC
Answered by Emily C. • Maths tutor
9788 Views

Find the derivative of the function y=3x^2e^(2x)sin(x).

y is the product of three different function, so we would use the product rule in order to calculate the derivative of the curve. In order to apply the product rule we need to find the derivatives of each of...
SR
Answered by Shreya R. • Maths tutor
7267 Views

f(x)=(2x+1)/(x-1) with domain x>3. (a)Find the inverse of f(x). (b)Find the range of f(x). (c) g(x)=x+5 for all x. Find the value of x such that fg(x)=3.

(a) Let y=f(x). Then y = (2x+1)/(x-1). Rearrange the equation to get x in terms of y to obtain the inverse function. This gives x=(1+y)/(y-2). So the inverse of f is f -1 (x)=(1+x)/(x-2) (b) Drawing a graph ...
LA
Answered by Lutfha A. • Maths tutor
6065 Views

In what circumstances should the present subjunctive be used in Spanish and how is it formed?

The subjunctive is a verb 'mood' in Spanish. There are many trigger phrases for the subjunctive and it can exist in both the present and imperfect (past) tense. However, today we will focus on just the prese...
MJ
Answered by Megan J. • Spanish tutor
2287 Views