Lesson Worksheet: Solving Equations Using Cofunction Identities Mathematics

In this worksheet, we will practice solving trigonometric equations using cofunction identities.


Find the value of sec(90+𝜃) given csc𝜃=178 where 0<𝜃<90.

  • A178
  • B817
  • C817
  • D178


Find the value of cot(270+𝜃) given tan𝜃=43 where 90<𝜃<180.

  • A43
  • B34
  • C43
  • D34


Find the value of cos(180+𝜃) given sin(90𝜃)=717 where 𝜃 is the smallest positive angle.

  • A41517
  • B717
  • C41517
  • D717


Find the general solution of the equation sin(90𝜃)=12.

  • A±𝜋6+2𝜋𝑛 where 𝑛
  • B±2𝜋3+2𝜋𝑛 where 𝑛
  • C±𝜋3+2𝜋𝑛 where 𝑛
  • D±5𝜋6+2𝜋𝑛 where 𝑛


Find the value of sintantan(180𝜃)+(90𝜃)(270𝜃) given cos𝜃=45 where 90<𝜃<180.

  • A35
  • B4915
  • C4915
  • D35


Find the value of sin(90𝜃) given sin𝜃=35 where 180𝜃<270.

  • A45
  • B35
  • C35
  • D45


Find the value of sin(270𝜃) given sin𝜃=1213 where 90<𝜃<180.

  • A513
  • B513
  • C1213
  • D1213


Find the value of cot𝜋22𝐵 given tan𝐵=32 where 3𝜋2<𝐵<2𝜋.

  • A56
  • B65
  • C125
  • D56


Find sin8𝜃 given sec(90+𝜃)2=0 where 180<𝜃<270.

  • A12
  • B3
  • C12
  • D32


Find the value of cot(𝜃90) given sec𝜃=1715 where 90<𝜃<180.

  • A815
  • B158
  • C815
  • D158

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