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integrate [xe^(-x)] with respect to x.

integrating a product of functions of x - integration by parts. integral of uv' = uv - integral of u'v. choice of u from LIATE - logs, inverse trig, algebra, trig, exponentials - choose u=x. u=x, v'=e^(-x). ...
ZP
Answered by Zachary P. • Maths tutor
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Two lines have equations r_1=(1,-1,2)+a(-1,3,4) and r_2=(c,-4,0)+b(0,3,2). If the lines intersect find c:

If the lines intersect the position vectors r_1 and r_2 must be equal at the point of intersection, so: (1,-1,2)+a(-1,3,4)=(c,-4,0)+b(0,3,2) which gives three equations for the three components: 1-a=c, -1+3a...
AZ
Answered by Aleksandar Z. • Maths tutor
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2x-4=6, find x.

[add 4 to both sides] 2x=10 Therefore, x=5
EW
Answered by Elena W. • Maths tutor
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solve the simultaneous equations , 5a+2b=23 & 9a-2b=19, algebraically.

find sum of both equations: 14a=42, therefore a=3, substitute 'a' into an equation: (5x3)+2b=23, therefore 2b=8, therfore b=4
RP
Answered by Rohan P. • Maths tutor
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find f'(x) of (x^2) + 3x + 2.

2x + 3
RP
Answered by Rohan P. • Maths tutor
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