Search our library of homework questions

Top answers

All subjects

All levels

Given that cos(x) = 1/4, what is cos(2x)?

cos(2x) = 2cos²(x) - 1 This is the identity. Therefore we can substitute in 2[cos²(x)] to be 2 multiplied by (1/4)².Therefore cos(2x) = 2(1/4)(1/4) - 1 = 2/16 - 1 = 2/16 -...

Answered by Bhumi K. • Maths tutor

8950 Views

Expand (2x+4)(x-3)

2x^2 - 2x - 12

Answered by Amy S. • Maths tutor

3969 Views

Compare anaerobic respiration in a yeast cell with anaerobic respiration in a muscle cell (3 marks)

READ the question - Anaerobic respiration in both 3 marks = give 3 differences/similaritiesyeast produces ethanol but muscles produce lactic acid (difference 1)yeast produces CO2 but muscles do not (MUST ...

Answered by Amy S. • Biology tutor

2520 Views

Is a strong acid the same as a concentrated acid?

They sound like they should mean something similar! However, chemistry uses words very carefully, and these words have very specific meanings. Strong acids completely dissociate in water....

Answered by Katharina B. • Chemistry tutor

8270 Views

What is the best structure to use in essays?

In your introduction, highlight the importance of the question in relation to the discipline of philosophy and outline a comparison of the points and scholars you will use to address the question. In the ...

Answered by Olga B. • Philosophy tutor

1631 Views