This in turn produces an unusual independence of mind, freeing the INTJ from the constraints of authority, convention, or sentiment for its own sake. INTJs are known as the Systems Builders of the types, perhaps in part because they possess the unusual trait combination of imagination and reliability.
Step 2 Use SOHCAHTOA to decide which one of Sine, Cosine or Tangent to use in this question. Step 3 For Sine calculate Opposite/Hypotenuse, for Cosine calculate Adjacent/Hypotenuse or for Tangent calculate Opposite/Adjacent. Step 4 Find the angle from your calculator, using one of sin-1, cos-1 or tan-1.
E.g., let the angle $\alpha_{23}$ between $a_2$ and $a_3$ be $90^\circ$. Then one diagonal $d$ can be computed by means of Pythagoras' theorem, and it remains to determine the angles of two triangles whose sides are known. This can be done using the cosine law. E.g., the cosine of the angle $\alpha_{41}$ is given by $$\cos\alpha_{41}={a_4^2+a_1^2-d^2\over 2 a_4 a_1}\ .$$.