1800-150-456-789
FlagBACK
Flag Trigonometry> Find the max and min value of cos*(45+x)+...
question mark

Find the max and min value of cos*(45+x)+(sinx-cosx)* (*means square)

Mayanksinha , 8 Years ago
Grade 11
anser 2 Answers
Vikas TU

Last Activity: 8 Years ago

 cos*(45+x)+(sinx-cosx)*

open the square ones,
=>  cos*(45+x)+((sinx)* + (cosx)* -2sinxcosx)
=>  cos*(45+x) + 1 – sin2x
now, maximum value for cos^2x is 1. and minimum zero.
and sin2x would have -1 when cos^2x is 1 and 1 when cos^2x is 0.
Because sinx and cos cannot have maximum and minimum value simulataneously .

Ajay

Last Activity: 8 Years ago

The maximum value of the function is 3 and minimum vaues is 0 as proved below.
using formula for cos2x and expanding the bracket the expression becomes
1/2[cos(pie/2 + 2x) + 1] + 1 – 2sinxcosx
= 1/2[-sin2x + 1]  + 1 -sin2x
= 3/2 -3/2sin2x
The maximum value is when sin2x = -1
max value = 3/2+ 3/2 = 3.
The mimimum value is when sin2x = 1
min value =3/2-3/2 = 0

Provide a better Answer & Earn Cool Goodies

star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments


Ask a Doubt

Get your questions answered by the expert for free

Other Related Questions on trigonometry

question mark
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
trigonometry
1 Answer Available

Last Activity: 2 Years ago

question mark
  • Find the general solution of equation tan3∂=cot2∂
For all angles between -720 and +720
trigonometry
0 Answer Available

Last Activity: 2 Years ago

question mark
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
trigonometry
0 Answer Available

Last Activity: 2 Years ago

question mark
cos^2 13ºcos^2 47º+cos^2 73º =? …..................
trigonometry
0 Answer Available

Last Activity: 3 Years ago

question mark
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
trigonometry
0 Answer Available

Last Activity: 3 Years ago