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Show that the set of real diagonal (n by n) matrices (with non-zero diagonal elements) represent a group under matrix multiplication

We must show that the set satisfies the group requirements: Identity, Closure, Associativity and Invertibility.Identity: Contains identity matrixAssociativity: Follows from the rules of matrix multiplication...
NP
3566 Views

solve the simultaneous equations: 3x + 5y = 4 ; 7x - 3y = 8

first recognise that if you double the first equation the both equations will be equal to 8.so now we have 6x + 10y = 8 ; 7x - 3y = 8now we can set the equations equal to each other to get 6x + 10y = 7x - 3y...
EW
Answered by Elizabeth W. • Maths tutor
4472 Views

differentiate: y=[xcos(x^3)]/[(x^4 + 1)^3] with respect to x

This question is on the trickier side as it is heavily computational and requires a good knowledge of the differentiation rules however it is a good way to practise using multiple rules at once.First we will...
EW
Answered by Elizabeth W. • Maths tutor
3283 Views

Find the volume of a right angled triangular prism with an angle of 28 degrees, hypotenuse of length 10 cm, and projected length of 12.5 cm. Give your answer in cm^3, to three significant figures.

The area of a prism is found by multiplying the area of the end face by the projected length. The adjacent and opposite side lengths of the triangle can be found using SOHCAHTOA. sin(28)= opposite/10, theref...
LM
Answered by Lily M. • Maths tutor
3932 Views

Solve Simultaneous equations: 3x + 4y = 23 & 2x + 3y = 16

We need to cancel one of the variables (the x or y) out. Find the LCM of x or y.e.g. for x --> 6Multiply the WHOLE eqn to get 6x. So multiply the 1st eqn by 2 and the 2nd by 3[1] 6x + 8y = 46[2] 6x + 9y =...
EE
Answered by Eric E. • Maths tutor
3859 Views