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Show that the equation 5sin(x) = 1 + 2 [cos(x)]^2 can be written in the form 2[sin(x)]^2 + 5 sin(x)-3=0

First, we need to realise that we will be using the trigonometric identity sin(x) 2 + cos(x) 2 = 1 As our goal is to end up with an equation involving only sin, we will therefore substitue cos(x) 2 with ( 1 ...
SG
Answered by Santiago G. • Maths tutor
18168 Views

Integrate the function : F'(x)=3x^2+4x-5

F'(x)=3x^2+4x-5 F(x)=(3/(2+1))(x^(2+1))+(4/(1+1)) (x^(1+1))-5(x^(0+1)) Answer: F(x)=x^3+2x^2-5x+c
IM
Answered by Ian Malique D. • Maths tutor
8587 Views

There are 5 white socks and 3 black socks in a draw. Steven takes out 2 at random. Work out the probability that Steven takes out 2 socks of the same colour.

P(WW) = 5/8 x 4/7 = 20/56 P(BB) = 3/8 x 2/7 = 6/56 P(same colour) = 20/56 + 6/56 = 26/56 = 13/28 (simplified)
TJ
Answered by Tom J. • Maths tutor
8978 Views

ABC is a right angled triangle. D is the point on AB such that AD = 3DB. AC = 2DB and angle A = 90 degrees. Show that sinC = k/√20 where k is an integer. Find the value of k

AB = 4DB AC = 2DB Find BC using Pythagoras: BC = √(4DB) 2 + (2DB) 2 BC = √20DB 2 = √20 DB sinC = opp/hyp = 4DB/√20DB = 4/√20 so k = 4
TJ
Answered by Tom J. • Maths tutor
16495 Views

Solve 7(k – 3) = 3k – 5

Step 1: 7k-21=3k-5 Step 2: 4k=16 Step 3: k=4
JY
Answered by Jin Yang Q. • Maths tutor
7863 Views