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Differentiate the function y = 26 + x - 4x³ -½x^(-4)

dy/dx = 1 - 12x² + 2x^(-5)
LM
Answered by Louix M. Maths tutor
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Why does as an excess of nutrients such as nitrates lead to animal death in bodies of freshwater?

This is an unexpected result as usually nutrients are considered beneficial to organisms. Some organisms do benefit enourmously from the nutrients, but this leads to the deaths of other. The high concentrati...
DA
Answered by Daniel A. Biology tutor
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Consider an isosceles triangle ABC, where AB=AC=1, M is the midpoint of BC, and <BAM=<CAM=x. Use trigonometry to find an expression for BM and by finding BC^2, show that cos2x = 1 - 2(sinx)^2.

Consider the right-angled triangle BAM. We have the hypotenuse and an angle, and want to find the opposite side. Therefore, using SOHCAHTOA, sinx = BM/1, hence BM = sinx. Because M is the midpoint of BC, BC ...
BS
Answered by Blessie S. Maths tutor
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How is immunity developed after a primary infection by bacteria?

Phagocytosis - A phagocyte detects the bacteria has foreign antigens and so envelops it with its cytoplasm, packaging it into a phagosome via endocytosis. Lysosomes then fuse with the phagosome releasing hyd...
DV
Answered by Daniel V. Biology tutor
2901 Views

In some parts of Africa, where malaria commonly occurs, there are higher frequencies of the allele that causes sickle-cell anaemia.

Individuals with the recessive sickle-cell anaemia allele have a lower chance of developing severe malaria. Therefore, they are more likely to survive and reproduce than those without the allele. The allele ...
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Answered by Laura N. Biology tutor
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