Find the Exact Value $\cos ^ { 2 } ( \pi / 8 ) - \sin ^ { 2 } ( \pi / 8 )$

question 7

Essay

Find the exact value. $\cos ^ { 2 } ( \pi / 8 ) - \sin ^ { 2 } ( \pi / 8 )$

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Definitions:

SSRIs

Selective Serotonin Reuptake Inhibitors, a class of drugs commonly prescribed for depression and anxiety disorders by increasing serotonin levels in the brain.

Interpersonal and Social Rhythm Therapy

A treatment method that helps people with bipolar disorder manage their moods by stabilizing daily rhythms such as sleep, wake, and meal times.

Bipolar Disorder

A mental disorder marked by extreme mood swings, including episodes of mania and depression.

Regular Routines

Consistent daily activities or habits that provide a structure and predictability to life, often contributing to improved mental health.