Two Sides of a Right Triangle ABC (C Is the Right

question 11

Multiple Choice

Two sides of a right triangle ABC (C is the right angle) are given. Find the indicated trigonometric function of the given
angle. Give exact answers with rational denominators.
-Find $\cos \mathrm { A }$ when $\mathrm { a } = \sqrt { 13 }$ and $\mathrm { c } = 10$ .

• A) \(\frac { 13 } { 10 }\)
• B) \(\frac { \sqrt { 87 } } { 10 }\)
• C) \(\frac { 87 } { 13 }\)
• D) \(\frac { \sqrt { 13 } } { 10 }\)

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Definitions:

Egocentrism

The inability to differentiate between one's own perspective and someone else's perspective.

Sensorimotor Stage

The first stage of Piaget's theory of cognitive development, where infants interact with the environment and learn through trial and error using their senses and motor skills.

Preoperational Stage

A stage of cognitive development in Piaget's theory, during which children from about 2 to 7 years of age develop and engage in symbolic play but struggle with logic and taking the perspective of others.

Concrete Operational

A stage in cognitive development in which children gain the ability to think logically about concrete events and objects.