The Basic Trignometry Technique

Well most of students on their first introduction to trigonometry generally fail to remember the basic values of all T- ratios from 0° to 90°during their practical application to practical solutions.Instead of foolishly mugging them up and memorizing them,here’s a simple way to know these values at your fingertips that will last forever in your memory. Example : Take sin o°,its value is √0/√4 = 0 sin 30° = √1/√4 = ½ sin 45° = √2/√4 = √1/√2 = 1/√2 sin 60° = √3/√4 = √3/2 Sin 90° = √4/√4 = 1 For cos values,write all in reverse order. i.e.cos o° = 1,cos 30° = √3/2,cos 45° = 1/√2, cos 60° = ½,cos 90° = 0 We know that tan A = sin A / cos A So, tan 0° = o/1 = 1 tan 30° = (1/2) / (√3/2) = 1/√3 tan 45° = (1/√2) / (1/√2) = 1

tan 60° = (√3/2) / (1/2) = √3 tan 90° = 1/0 =

(Infinity)

for cosec A = 1/sin A for sec A = 1/cos A for cot A = 1/ tan A Also , 1 /

T value s sin cos tan cosec sec cot

=0

0°

30°

45°

60°

90°

0 1 0

1/2 √3/2 1/√3 2 2/√3 √3

1/√2 1/√2 1 √2 √2 1

√3/2 1/2 √3 2/√3 2 1/√3

1 0

1

1 0

Hope the above calculations offer you some amount of substantial help.