Trig Identities
and Equations
Twitter: @Owen134866
www.mathsfreeresourcelibrary.com
, Prior Knowledge Check
1a) Sketch the graph of for 3) Solve these equations
b) How many solutions are there to a)
the equation in the range ?
1, 3
4 write down
c) Given that (to 3sf), b)
three other solutions to the
equation
1, -9
c)
143.1, 396.9, 503.1
2) Solve the equation
3 ± √ 65
4
-44.4
,Teachings For
Exercise 10A
, Trig Identities and Equations
You need to understand how to
use the trig graphs to find other y y = sinθ
values of sine, cosine or tan -40 -40
1
50 130
You need to be able to work out
larger values of sin, cos and tan as
acute angles (0º - 90º) 0 θ
90º 180º 270º 360º
Write sin 130º as sine of an acute -1
angle
(sometimes asked as a
‘trigonometric ratio’)
Draw a sketch of the graph
Sin 130º = Sin 50º Mark on 130º
Using the fact that the graph has symmetry, find an
acute value of θ which has the same value as sin 130
10A
and Equations
Twitter: @Owen134866
www.mathsfreeresourcelibrary.com
, Prior Knowledge Check
1a) Sketch the graph of for 3) Solve these equations
b) How many solutions are there to a)
the equation in the range ?
1, 3
4 write down
c) Given that (to 3sf), b)
three other solutions to the
equation
1, -9
c)
143.1, 396.9, 503.1
2) Solve the equation
3 ± √ 65
4
-44.4
,Teachings For
Exercise 10A
, Trig Identities and Equations
You need to understand how to
use the trig graphs to find other y y = sinθ
values of sine, cosine or tan -40 -40
1
50 130
You need to be able to work out
larger values of sin, cos and tan as
acute angles (0º - 90º) 0 θ
90º 180º 270º 360º
Write sin 130º as sine of an acute -1
angle
(sometimes asked as a
‘trigonometric ratio’)
Draw a sketch of the graph
Sin 130º = Sin 50º Mark on 130º
Using the fact that the graph has symmetry, find an
acute value of θ which has the same value as sin 130
10A
