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If we have a vector 4x + 6y + z and another vector 3x +11y + 2z then what is the angle between the two?Give the answer in radians

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Answered by Matthew S. • Maths tutor

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What are the important similarities and differences between RNA and DNA?

Similarities Nucleotides consist of pentose sugar, phosphate and base

Differences RNA: ribose (sugar) single stranded Made in the nucleus but can move outside it U, A, G, C bases

DNA: deoxyr...

Answered by Rosie L. • Biology tutor

5492 Views

Express 3cos(x)+4sin(x) in the form Rsin(x+y) where you should explicitly determine R and y.

Since Rsin(x+y)=Rsin(x)cos(y)+Rsin(y)cos(x), we can set Rcos(y)=4 (1) and Rsin(y)=3 (2) on comparison to the desired equation. Considering (2) divided by (1) we see that tan(y)=sin(y)/cos(y)=3/4 so y=atan...

Answered by William V. • Maths tutor

11829 Views

What is the difference between allopatric and sympatric speciation?

Allopatric speciation occurs when populations of a species are separated by a physical barrier - this could be a river for animals that cannot swim, for example. Separation of the populations means that t...

Answered by Tom M. • Biology tutor

65139 Views

What is the structure and function of DNA?

DNA (deoxyribonucleic acid) is a double helix composed of units called nucleotides. Each nucleotide is composed of a single deoxyribose sugar, a phosphate group and one of four nitrogen bases. The 4 bases...

Answered by Sylvia D. • Biology tutor

4141 Views